PROTOTYPE CONTEXTUALIZED DAILY LESSON PLANS IN GRADE 11/12 STATISTICS AND PROBABILITY i ii LIST OF DEVELOPMENT TEAM MEMBERS PROTOTYPE AND CONTEXTUALIZED DAILY LESSON PLANS IN GRADE 11/12 (STATISTICS AND PROBABILITY) WRITERS MILADEN DESPABILADERAS ERLYN M. LACSA ANALYN M. VELOSO ADELFA C. DITAN RICHELLE D. DIONEDA MA. JECCA L. AZAS RUEL G. FRAGO MA. CIELO BERMUNDO MICHAEL DOMANAIS JASMIN A. JAO PINKY D. DESTACAMENTO MARKSON B. MEJIA AMORY R. BORINGOT KATHLEEN DUCAY ARWIN D. BONTIGAO NELVIN EBIO CATHERINE GERONIMO DEMONSTRATION TACHERS TITO GUATNO ERLYN M. LACSA RUEL G. FRAGO AMORY R. BORINGOT MARILYN HULAR RICHELLE DIONEDA KATHLEEN DUCAY PINKY O. DESTACAMENTO JASMIN A. JAO ANNALYN M. VELOSO MARKSON B. MEJIA JECCA AZAS MILADEN DESPABILDERAS ARWIN BONTIGO EDITORS MA. THERESA DUAZO ROWENA H. BORJA ELENA D. HUBILLA Education Program Supervisor-1 Mathematics MONSERAT D. GUEMO, Ph. D. CID Chief Supervisor MARIVIC P. DIAZ, Ed. D. OIC, Assistant Schools Division Superintendent Dr. NYMPHA D. GUEMO Schools Division Superintendent iii iv School Teacher Grade Level Learning Area Time & Date Quarter 11 Statistics and Probability 3rd I.OBJECTIVES A. Content Standards B. Performance Objective C. Learning Competencies/ Objectives ( Write the LC code for each) II.CONTENT III.LEARNING RESOURCES A. References 1.Teachers Guide pages 2.Learners Material Pages 3. Textbook Pages B. Other Learning Resources IV. PROCEDURE A. Reviewing past lesson or Presenting the new lesson The learner demonstrates understanding of key concepts of random variables and probability distributions. The learner is able to apply an appropriate random variable for a given real-life problem (such as in decision making and games of chance). The learner illustrates a random variable (discrete and continuous). (M11/ 12SP- IIIa-1) The learner distinguishes between a discrete and continuous random variable. (M11/ 12SP – IIIa-2) EXPLORING RANDOM VARIABLES Statistics and probability Rene R. Belecina, Elisa S. Bacacay, Efren B. Mateo,pp.2 –8 Worksheets COUNTABLE or MEASURABLE? Identify whether the given situation is countable or measurable. The students will raise their right hand if the situation is countable, left if it is measurable. 1. Number of students inside the classroom 2. Amount of salt needed to cook chicken tinola 3. Number of likes your recent post received 4. Capacity of an auditorium 5. Length of the chalkboard 1 B. Establishing a purpose of the new lesson The teacher should have summarized the learners’ answers in the previous activity as follows: COUNTABLE Number of students inside the classroom Number of likes your recent post received MEASURABLE Amount of salt needed to cook tinola Capacity of an auditorium Length of chalkboard C. Presenting Examples/ instances of the new lesson D. Discussing new concepts and practicing new skills no.1. Let the learners identify the key words identifying countable and measurable variables. 1. The teacher will discuss what variable is. A variable is a characteristic that is observable or measurable in every unit of the universe. Variables can be broadly classified as either qualitative or quantitative. And quantitative can be classified into discrete and continuous. 2. The students will be asked to determine the variables in the activity they performed. 3. The teacher will explain quantitative and qualitative variables, as well as discrete and continuous variables. 4. Let the students classify discrete and continuous variables from the given situations in the activity. CREATE YOUR GROUP PROFILE To create a group profile in statistics class, the members of each team will fill up the following data: NAME OF THE STUDENT GENDER AGE NUMBER OF SIBLINGS DAILY ALLOWANCE RELIGION HEIGHT IN CM WEIGHT IN KG FINAL GRADE IN GENERAL MATH SUBJECT After gathering the data, each team will make a creative group profile on a cartolina. RUBRICS: ORGANIZATION OF THE DATA – 15 CREATIVITY – 10 TOTAL: 25 The students will make a summary on the classifications of the data gathered in their group profile through a table. QUANTITATIVE QUALITATIVE Age Name of student Number of siblings Gender Daily allowance Religion Height in cm Weight in kg Final grade in General Math 2 Guide Questions: 1. When do you say that the variable is qualitative? 2. When do you say that the variable is quantitative? 3. Among the quantitative variables, which are discrete? Why? 4. Among the quantitative variables, which are continuous? Why? E. Discussing new concepts and practicing new skills no.2 The students will classify the listed quantitative variables in the activity CREATE YOUR GROUP PROFILE as discrete or continuous by putting the data in the correct column. DISCRETE CONTINUOUS Height in cm Weight in kg Final grade in Gen. Math Age Number of siblings Daily allowance The teacher will discuss what discrete and continuous variables are. A random variable is a discrete random variable if its set of possible outcomes is countable. A random variable is a continuous random variable if it takes on values of a continuous scale. Often, continuous random variables represent measured data, such as heights, weights and temperatures. F. Developing Mastery (Leads to Formative Assessment 3.) WHAT AM I? The students will classify the listed quantitative variables below as discrete or continuous by putting the data in the correct column. 1.the number of patients attributed to dengue 2. the average amount of electricity consumed per household per month 3. the number of patient arrivals per hour at a hospital 4. the number of voters who reported for registration 5. the amount of sugar in a cup of coffee DISCRETE The number of patients attributed to dengue the number of patient arrivals per hour at a hospital the number of voters who reported for registration G. Finding practical application of concepts and skills in daily living CONTINUOUS The average amount of electricity consumed per household per month the amount of sugar in a cup of coffee Make a survey regarding the use of cellphone of 5 of your classmates using the following variables. For each of them, classify the qualitative and the quantitative. Distinguish a quantitative variable as to discrete or continuous. 1. Number of family members with cellphone 2. Type of ownership 3. Length (in minutes) of longest call made on each cellphone 3 4. Amount paid for cellphone load per month H. Making Generalization and abstraction about the lesson 1. How do you classify quantitative and qualitative variable? 2. How do you distinguish discrete and continuous variable? I. Evaluating learning Classify whether the variable is qualitative or quantitative. If quantitative, distinguish if discrete or continuous. ADVANCED LEARNERS 1. the number of dropouts in a school for a period of 10 years 2. the number of defective computers produced by a manufacturer per year 3. the number of points scored in a basketball game 4. the heights of a varsity players in a school in meters 5. the length of time spent in playing video games in minutes J. Additional activities for application and remediation AVERAGE LEARNERS 1. gender of athletes for Palarong Bikol 2. speed of a car 3. number of school days per semester 4. the number of accidents per year in an intersection 5. the number of deaths attributed to lung cancer Reflection: In life, what are countable treasures? What are measurable treasures? If you are to choose, which do you prefer to keep, countable or measurable treasures? Why? V- REMARKS VI-REFLECTION VII-OTHERS A. No. of learners who earned 80% in the evaluation B. No. of learners who require additional activities for remediation who scored below 80% C. Did the remedial lessons work? No. of learners who have caught up with the lesson D. No. of learners who continue to 4 require remediation E. Which of my teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/discover which I wish to share with other teachers? 5 School Teacher Grade Level Learning Area Time & Date Quarter 11 Statistics and Probability 3rd I.OBJECTIVES A. Content Standards B. Performance Objective C. Learning Competencies/ Objectives ( Write the LC code for each) II.CONTENT III.LEARNING RESOURCES A. References 1.Teachers Guide pages 2.Learners Material Pages 3. Textbook Pages B. Other Learning Resources IV.PROCEDURE A. Reviewing past lesson or Presenting the new lesson The learner demonstrates understanding of key concepts of random variables and probability distributions. The learner is able to apply an appropriate random variable for a given real-life problem (such as in decision making and games of chance). The learner finds the possible values of a random variable. ( M11/12SP – IIIa-3) EXPLORING RANDOM VARIABLES Statistics and probability Rene R. Belecina, Elisa S. Baccay, Efren B. Mateo, pp.2 8 Each team will perform an experiment using coins and dice to answer the following questions. An answer board is provided for each team. Every correct answer is equivalent to 5 points. The three teams with the highest score will be declared winners. 1. In how many ways can a coin fall?2 2. In how many ways can a die fall?6 3. In how many ways can two coins fall?4 4. In how many ways can two dice fall?36 B. Establishing a purpose of the new lesson GIVE ME MY SAMPLE SPACE Each team will complete the table by identifying the sample space for the given event. EVENT 1. Tossing a coin 2. Rolling a die SAMPLE SPACE H,T 1,2,3,4,5,6 (H,T), (H,H), (T,H), (T,T) (1,1),(1,2),(1,3),(1,4),(1,5),(1,6) (2,1),(2,2),(2,3),(2,4),(2,5),(,6) (3,1),(3,2),(3,3),(3,4),(3,5),(3,6) (4,1),(4,2),(4,3),(4,4),(4,5),(4,6) 3. Tossing two coins 4. Rolling two dice 6 (5,1),(5,2),(5,3),(5,4),(5,5),(5,6) (6,1),(6,2),(6,3),(6,4),(6,5),(6,6) Guide Questions: 1. How many outcomes did you have in tossing a coin? 2. How many outcomes did you have in rolling a die? 3. How many outcomes did you have in tossing two coins? 4. How many outcomes did you have in rolling two dice? 5. How did you represent the outcomes of each event? This activity leads you to the understanding of Sample Space and Finding the Value of the Random Variable. C. Presenting Examples/ instances of the new lesson Two dice are rolled. Let X be the random variable representing the 6 spots/dots that occur. Find the value of random variable X. SAMPLE SPACE 1,1 1,2 1,3 1,4 1,5 1,6 2,1 2,2 2,3 2,4 2,5 2,6 3,1 3,2 3,3 3,4 3,5 3,6 4,1 4,2 4,3 4,4 4,5 4,6 5,1 5,2 5,3 5,4 5,5 5,6 6,1 6,2 6,3 7 VALUE OF THERANDOM VARIABLE X 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 1 1 1 1 6,4 6,5 6,6 1 1 2 The value of random variable X are 0,1 and 2 D. Discussing new concepts and practicing new skills no.1 The teacher will discuss how to find the Value of Random Variable. E. Discussing new concepts and practicing new skills no.2 Suppose an experiment is conducted to determine the distance that a certain type of car will travel using 10 L of gasoline over a prescribed test course. If distance is a random variable, can you determine the value of random variable? Why? Why not? Lead the students to understanding on continuous random variable. F. Developing Mastery (Leads to Formative Assessment 3.) Three coins are tossed. Let Z be the random variable representing the number of heads that occur. Find the values of the random variable Z. SAMPLE SPACE H,H,H H,H,T H,T,H H,T,T T,H,H T,H,T T,T,H T,T,T VALUE OF THERANDOM VARIABLE Z 3 2 2 1 2 1 1 0 The value of the random variable Z are 0,1,2 and 3 G. Finding practical application of concepts and skills in daily living Suppose a cellphone buyer wants to buy four units of cellphones. Randomly, how would he know that the cellphone he chose is defective or not? Let D represent the defective cellphone and N represents the non-defective cellphone. If we let X be the random variable representing the number of defective cellphones, show the values of the random variable x. Complete the table below to show the values of the random variable. SAMPLE SPACE D,D,D,D D,D,D,N D,D,N,D D,D,N,N D,N,D,D D,N,D,N VALUE OF THE RANDOM VARIABLE X (number of defective cellphones) 4 3 3 2 3 2 8 D,N,N,D D,N,N,N N,D,D,D N,D,D,N N,D,N,D N,D,N,N N,N,D,D N,N,D,N N,N,N,D N,N,N,N 2 1 3 2 2 1 2 1 1 0 The value of the random variable X are 0,1,2,3and 4. H.Making Generalization and abstraction about the lesson I. Evaluating learning How do you find the values of a random variable? Find the possible values of the random variable. ADVANCED LEARNERS From a box containing 4 black balls and 2 green balls, 3 balls are drawn in succession. Each ball is placed back in the box before the next draw is made. Let G be a random variable representing the number of green balls that occur. Find the values of the random variable G. POSSIBLE VALUE OF RANDOM VARIABLE G OUTCOMES AVERAGE LEARNERS A shipment of five computers contains two that are slightly defective. If a retailer receives three of these computers at random, list the elements of the possible outcomes using D for defective and N for non- defective computers. To each sample point assign a value x of random variable x of the random variable X representing the number of computers purchased by the retailer which are slightly defective. Find the values of the random variable X. POSSIBLE OUTCOMES VALUE OF RANDOM VARIABLE G J. Additional activities for application and remediation 9 V- REMARKS VI-REFLECTION VII-OTHERS A. No. of learners who earned 80% in the evaluation B. No. of learners who require additional activities for remediation who scored below 80% C. Did the remedial lessons work? No. of learners who have caught up with the lesson D. No. of learners who continue to require remediation E. Which of my teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/discover which I wish to share with other teachers? 10 School Teacher Grade Level Learning Area Time & Date Quarter I. OBJECTIVES A. Content Standard B. Performance Standard C. Learning Competencies/ Objectives II. III. CONTENT LEARNING RESOURCES A. References 1. Teacher’s guide pages 2. Learner’s material pages 3. Textbook Pages 4. Additional materials from learning resource (LR) portal: B. Other Learning Resources IV. PROCEDURES A. Reviewing previous lesson or presenting new lesson 11 Statistics and Probability 3rd The learner demonstrates understanding of key concepts of random variables and probability distributions. The learner is able to apply an appropriate random variable for a given real-life problem (such as in decision making and games of chance). The learner is able to: Illustrate a probability distribution for a discrete random variable and its properties. M11/12SPIIIa-4 Construct the probability mass function of a discrete random variable and its corresponding histogram. M11/12SP-IIIa-5 Compute probabilities corresponding to a given random variable. M11/12SP-IIIa-6 CONSTRUCTING PROBABILITY DISTRIBUTION 117-127 NONE NONE Statistics and Probability by Rene R. Belecina, Elisa S. Bacacay, and Efren B. Mateo Ask the learners to provide information on how many siblings they have by asking them to raise their hands as the teacher calls the no. of siblings they have by starting with 0,1,2,.. No. of Frequency Relative Siblings Frequency 0 1 2 3 4 5 6 7 8 11 9 10 Total: Draw a histogram to represent relative frequency. Emphasize that the values on the y- axis represent these relative frequencies (in percent). Have them add the areas, and show that the sum is 100%. Ask them if this is a coincidence or this is expected? B. Establishing a purpose for the lesson C. Presenting examples/instances of the new lesson Present the objectives of the lesson: Illustrates a probability distribution for a discrete random variable and its properties. Constructs the probability mass function of a discrete random variable and its corresponding histogram. Computes probabilities corresponding to a given random variable. Introduce the properties of the probability. Properties of Probability Distributions of Discrete Random Variable 1. The probability of each value of the random variable must be between or equal to 0 and 1. In symbol, we write it as 0 ≤ P(x) ≤ 1. 2. The sum of the probabilities of all values of the random variable must be equal to 1. In symbol, we write it as ∑ P(x) = 1. Present the example. Suppose three coins are tossed. Let Y be the random variable representing the number of tails that occur. Find the probability of each values of the random variable Y. Solution: STEPS 1. Determine the sample space. Let H represent head and T represent Tail. 2. Count the number of tails in each outcome in the sample space and assign a number to this outcome. 12 SOLUTION The sample space for this experiment is: S= {TTT, TTH, THT, HTT, HHT, HTH, THH, HHH)} Possible Outcomes TTT TTH THT HTT HHT Value of the Random Variable Y (Number of tails) 3 2 2 2 1 3. Write the possible values of the random variable Y representing number of tails. Assign probability Values P(Y) to each value of the random variable. HTH THH HHH Number of tails (Y) 0 1 2 3 1 1 0 Probability P(Y) 1/8 3/8 3/8 1/8 The probability Distribution or the Probability Mass function of Discrete Random Variable Y Number of tails Y Probability P(Y) D. Discussing new concepts and practicing new skills #1 0 1/8 1 3/8 2 3/8 3 1/8 The students will look for a partner and distribute a worksheet for each pair. Let T be a random variable giving the number of heads in three tosses of a coin. List the elements of the sample space S for the three tosses of the coin and find the probability of each of the values of the random variable T. (10 mins) 13 STEPS 1. Determine the sample space. 2. Count the number of heads in each outcome in the sample space and assign this number to this outcome. SOLUTION S= {TTT, TTH, THT, HTT, HHT, HTH, THH, HHH)} Possible Value of the Outcome Random s Variable T(Number of heads) TTT TTH THT HTT HHT HTH THH HHH 0 1 1 1 2 2 2 3 3. Write the number of possible values and assign probability values to each random variable. Number Probability of of P(T) heads (T) 0 1/8 1 3/8 2 3/8 3 1/8 Make a probability Mass Function of Discrete Random Variable T. Number of Heads (T) 0 Probability 1/8 P(T) Construct a Histogram. 14 1 2 3 3/8 3/8 1/8 Call two volunteer pairs to share their output to the class. E. Discussing new concepts and practicing new skills #2 F. Developing mastery The students will form 5 groups and the teacher will provide the worksheet to each group. The group activity is good for 15 mins. Two balls are drawn in succession without replacement from an urn containing 5 red balls and 6 blue balls. Let Z be the random variable representing the number of blue balls. Construct the probability distribution of the random variable Z. STEPS 1. Determine the sample space. 2. Count the number of blue balls in each outcome in the sample space and assign this number to this outcome. SOLUTION S= { RR, RB, BR, BB } Possibl e Outco mes RR RB BR BB 3. Write the number of possible values and assign probability values to each random variable. Probabili ty P(Z) ¼ ½ ¼ Make a probability Mass Function of Discrete Random Variable Z. Number of blue balls (Z) Probability P(Z) Number of Blue Balls (Z) 0 1 2 Value of the Random Variable Z (Number of Blue Balls) 0 1 1 2 Construct a Histogram. 15 0 1/4 1 1/2 2 1/4 G. Finding practical applications of concepts, and skills in daily living Let them post their output on the board and each group will critic the output of the other group. Practical Application The daily demand for copies of a newspaper at a variety store has the probability distribution as follows: Number of copies X Probability P(X) 0 0.06 1 0.14 2 0.16 3 0.14 4 0.12 5 0.10 6 0.08 7 0.07 8 0.06 9 0.04 10 0.03 What is the probability that three or more copies will be demanded in a particular day? 0.64 or 64 % What is the probability that the demand will be at least two but not more than six? 0.6 or 60% H. Making generalization I. Evaluate learning How do you construct probability distribution? How do you make the histogram for a probability distribution? Give the steps in constructing the histogram for a probability distribution. The following data show the probabilities for the number of Banana Chipssold in SHS Canteen: Number of Banana Chips 0 1 2 3 4 5 6 7 8 9 10 a. Find P(X≤ 2) =0.5 b. Find P(X≥ 7)=0.13 c. Find P(1≤ X ≤ 5)= 0.81 16 Probability P(x) 0.100 0.150 0.250 0.140 0.090 0.080 0.060 0.050 0.040 0.025 0.015 d. Construct a histogram V. REMARKS VI. REFLECTION A. No. of learners who earned 80% in the evaluation B. No. of learners who require additional activities for remediation who scored below 80% C. Did the remedial lessons work? No. of learners who have caught up with the lesson D. No. of learners who continue to require remediation E. Which of my teaching strategies worked well? Why did this works? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/discover which I wish to share with other teachers? 17 School Grade Level Learning Area Quarter Teacher Time & Date I – OBJECTIVES A. Content Standards B. Performance Standard C. Learning Competencies/ Objectives3 II – CONTENT III – LEARNING RESOURCES A. References 1. Teacher’s Guide pages 2. Learners’ Materials 3. Textbook pages 4. Additional Materials from Learning Resource (LR) portal 5. Other Learning Resources IV – PROCEDURE A. Reviewing past lesson or presenting the new lesson Eleven Statistics and Probability Third Quarter The learner demonstrates understanding of key concepts of random variables and probability distributions. The learner is able to apply an appropriate random variable for a given real-life problem (such as in decision making and game of chance). The learner illustrates and calculates the variance of a discrete random variable. M11/12SP-IIIb-1, M11/12SP-IIIb-2 The learner interprets the variance of a discrete random variable. M11/12SPIIIb-3 The learner solves problems involving the variance of a discrete random variable. M11/12SP-IIIb-4 Computing the Variance of a Discrete Random Variable 31 - 40 Statistics and Probability (Rex Book Store) by: Rene R. Belecina 1. Start the lesson by “The Longer the Better Game” Mechanics: a. Group the class into 4 or 5 groups b. Give each group a printed pictures of bananas c. Each group will measure the sizes of the bananas d. They will compute the mean, variance and standard deviation of the data gathered 18 e. The group that finishes first will be the winner. Ask: How do you get the mean, the variance and the standard deviation? (Recall that the average of a given set of data is a measure of central tendency. Inform them that the expected value – being an average – measures the center of the distribution of the possible values of X.) The variance and standard deviation describe the amount of spread, dispersion, or variability of the items in a distribution. So using the standard deviation we have a “standard way of knowing what is normal, what is extra large or extra small. B. Establishing a purpose for the new lesson Ask: How do you describe the spread or dispersion in a probability distribution? Our lesson for today will teach us how to compute the variance and standard deviation of a discrete probability distribution. C. Presenting Present a contextualized problem to the class. examples/instances The number of pentel pens sold per day of the new lesson at the canteen, along with its probabilities, is shown in the table posted on the board. Compute the variance and the standard deviation of the probability distribution by following the given steps. Number of Pentel Probability Pens Sold (X) P(X) 1 0 10 2 1 10 3 2 10 2 3 10 2 4 10 19 D. Discussing new concepts and practicing new skill #1 (After filling in the table, add another column on the right and let the class subtract the mean from the value of the random variable X) No. of Pentel Pens Sold (X) Probability 𝑋 ∙ 𝑃(𝑋) 𝑋− 𝜇 0 0 – 2.2 = - 2.2 P(X) 1 10 2 10 3 10 2 10 2 10 0 1 2 3 4 2 10 6 10 6 10 8 10 1 – 2.2 = 1.2 2 – 2.2 = -0.2 3 – 2.2 = 0.8 4 – 2.2 = 1.8 (Let them square the result an write it on the column added in the right side) No. of Pentel Pens Sold (X) P(X) 𝑋 ∙ 𝑃(𝑋) 𝑋 − 𝜇 0 - 2.2 4.84 1.2 1.44 -0.2 0.04 0.8 0.64 1.8 3.24 1 10 2 10 3 10 2 10 2 10 0 1 2 3 4 2 10 6 10 6 10 8 10 (𝑋 − 𝜇) 2 (Let the students multiply the result in the 5th column by the corresponding probability P(X)) No. of Pentel Pens Sold (X) P(X) 0 1 10 20 𝑋 ∙ 𝑃(𝑋) 0 𝑋 − 𝜇 - 2.2 (𝑋 − 𝜇)2 (𝑋 − 𝜇)2 ∙ 𝑃(𝑋) 4.84 0.484 1 2 3 4 2 10 3 10 2 10 2 10 2 10 6 10 6 10 8 10 1.2 1.44 0.288 -0.2 0.04 0.012 0.8 0.64 0.128 1.8 3.24 0.648 (Tell the students to get the sum in the 6the column) 𝜎 2 = ∑(𝑥 − 𝜇 )2 ∙ 𝑃(𝑋) = 1.56 This is now the variance of the probability distribution Ask: - How do we get the standard deviation? To get the standard deviation, simply get the square of the variance. E. Discussing new concepts and practicing new skill #2 (Present the alternative Procedure in Finding the Variance and Standard Deviation of a Probability Distribution found in page 35 of the textbook.) F. Developing Mastery Ask: What does the variance tell us? How about the standard deviation? G. Finding practical applications of concepts and skills in daily living Present a sample word problem to the class. (The teacher will decide if the activity will be done by pair or by group) When three coins are tossed, the probability distribution for the random variable X representing the number of heads that occur is given below. Compute the variance and the standard deviation of the probability distribution. 21 Number of Heads (X) Probability P(X) 0 1 2 3 H. Making Generalization 1 8 3 8 3 8 1 8 (Checking of output) Ask: -What does the variance of the probability distribution tell us? -How do you interpret the variance of a probability distribution? -How do you get the variance of discrete random variable? -How do you get the standard deviation of discrete random variable? (Solicit ideas/answers from the class and post it on the board) (Present the formula for the variance of the discrete random variable) Formula for the Variance and Standard Deviation of a Discrete Probability Distribution The variance of a discrete random variable with a discrete probability distribution is given by the formula: 𝜎 2 = ∑(𝑥 − 𝜇 )2 ∙ 𝑃 (𝑋) The standard deviation of a discrete random variable with a discrete probability distribution is given by the formula: 𝜎 2 = √(𝑋 − 𝜇 )2 ∙ 𝑃(𝑋) where: X = value of the random variable P(X) = probability of the random variable X 𝜇 = mean of the probability distribution 22 I. Evaluate learning (The teacher will distribute an activity sheet for the evaluation) Solve. Find the variance and standard deviation of the probability distribution of the random variable X, which can take only the values 1, 2 and 3, 10 given the P(1) = 33, 1 12 P(2) = 3, and P(3) = 33. J. Additional Activities V. REMARKS VI. OTHERS A. No. of learners who earned 80% in the evaluation B. No. of learners who require additional activities for remediation who scored below 80% C. Did the remedial lesson worked? No. of learners who have caught up with the lesson D. No. of learners who continue to require remediation E. Which of the teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I used/discover which I wish to share with other teachers? 23 School Grade Level Learning Area Quarter Teacher Time & Date Eleven Statistics and Probability Third Quarter I. OBJECTIVES A. Content Standards B. Performance Standards C. Learning Competencies / Objectives (Write the LC code for each) II. CONTENT III. LEARNINGRESOURCES A. References 1. Teacher’s Guide pages 2. Learner’s Materials pages 3. Textbook pages 4. Additional Materials for Learning B. Other Learning Resources The learner demonstrates understanding of key concepts of normal probability distribution. The learner is able to accurately formulate and solve real-life problems in different disciplines involving normal distribution. The learner illustrates a normal random variable and its characteristics.( M11/12SP-IIIc-1) The learner construct normal curve (M11/12SP-IIIc-2) Specific Objectives: 1. Illustrate a normal random variable 2. Determine / enumerate the characteristics of a normal random variable / probability distribution. 3. Cite real- life examples involving normal distribution. 4. Sketch / Construct a normal curve which represents a normal distribution. Normal Probability Distribution and its Characteristics Next Century Mathematics (Statistics and Probability) Senior High School by Jesus P. Mercado pages 308-321 Statistics and Probability by Rene R. Belecina et. Al. First Edition IV. PROCEDURES A. Reviewing I. Ask the leader of the day to do the routinely activities: a. lead the prayer previous lesson or presenting the b. do the head counting new lesson c. recapitulation of the previous lesson (the teacher thank the leader of the day’s effort) II. Ask the students to do the activity “Let’s be United” (refer to sheet no. 1) 24 Group Activity Students are to form a figure out of the pieces of the puzzle Group1: Graph skewed to the right Group 2:Graph skewed to the left Group 3:Graph of a normal distribution Group4: Sketch of a negatively skewed Group 5: Sketch of a positively skewed Group 6: Sketch of a normal curve III. Class discussion: The teacher facilitates the discussion on the different aspects or characteristics of each graph/ sketch/ figure through the following questions: 1. What have you formed? Say something about the figure. 2. Is there similar graphs? In what sense? 3. If we are to group the graphs / figures you formed, which should be together? 4. How do these grouped figures differ from the other groups? (for a bigger class the teacher can select representatives to do the activity especially those who were identified as good performers in class, then the rest of the class observes) B. Establishing a purpose for the lesson The teacher would say: “Today we are guided by the following objectives … “ A. The teacher presents a power point (any visual) of the objectives of the lesson. B. (The presentation of today’s rule during class discussion is encouraged if any) C. Presenting examples/ instances of the new lesson A. Based on the observations from the previous activity the teacher discusses the difference among the positively and negatively skewed and the graph of normal distribution. (Mention that there are so many continuous random variables, such as IQ scores, heights of people, or weights have histograms that have bell-shaped distributions.) B. Show them the picture to let them see the real- life application of the normal curve. 25 1. What have you noticed with the picture shown? 2. If we are to locate the middle part, what can you say on the left or right part of the figure? 3. Is the given figure best describes a normal probability distribution? Why? C. Discussing 1. Let the students watch the video on normal new concepts distribution and its properties and practicing (the students has to take down notes on the new skills #1 properties) 2. Discussion of the properties (this can be done through the video or after watching the video) 3. (include) Draw a picture of the normal (bellshaped) curve Emphasize the following statements about the normal curve: • The total area under the normal curve is equal to 1. • The probability that a normal random variable X equals any particular value a, P(X=a) is zero (0) (since it is a continuous random variable). • Since the normal curve is symmetric about the mean, the area under the curve to the right of m equals the area under the curve to the left of m which equals ½, i.e. the mean m is the median. Emphasize also to learners that every normal curve (regardless of its mean or standard deviation) conforms to the following "empirical rule" (also called the 68-95-99.7 rule): • About 68% of the area under the curve falls within 1 standard deviation of the mean. • About 95% of the area under the curve falls within 2 standard deviations of the mean. • Nearly the entire distribution (About 99.7% of the area under the curve) falls within 3 standard deviations of the mean. 4. Explain that the graph of the normal distribution depends on two factors: the mean m and the standard deviation σ. 5. D. Discussing Sketching Normal Curve new concepts The teacher shows the normal curve to the class and and practicing the process on how to sketch the curve. (the teacher new skills #2 26 should give emphasis on the properties of the normal curve) E. Developing mastery (Leads to Formative Assessment 3) A. Present the properties through PPT then ask the students to perform the activity with the group of 10 students (any desired group size of the teacher): Group 1: Sketch a normal curve then label the parts of the curve showing the properties of the curve.(puzzle like or anything related to arts) Group 2: Create a convo (conversation about the properties of the normal distribution ) Group 3: Make a Jingle of about the properties of the normal distribution. *The teacher can add other skills/ talents of the students ass observed by the teacher. F. Finding practical Let students cite some example in real- life where applications of concepts they can see the normal curve or distribution. and skills in daily living G. Making generalization Let them answer the question; s and abstractions “What are the properties of the normal distribution?” about the lesson H. Evaluating Distribute sheet 1 to the students. Learning V. REMARKS VI. REFLECTION A. No. of learners who earned 80% in the evaluation. B. No. of learners who require additional activities for remediation who scored below 80%. C. Did the remedial lessons work? No. of learners who have caught up with the lesson. 27 D. No. of learners who continue to require remediation E. Which of my teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/discover which I wish to share with other teachers? Evaluation Test I. TRUE OR FALSE: 1. The standard normal distribution is also called normal curve. 2. The area under a normal curve is 100. 3. The mean of a standard normal curve is 3. 4. The curve of a normal distribution extends indefinitely at the tails. 5. The shape of the normal probability distribution is symmetric about the mean. Test II Give and label each normal curve below with the correct characteristics / properties. 28 School Grade Level Learning Area Quarter Teacher Time & Date Eleven Statistics and Probability Third Quarter I. OBJECTIVES A. Content Standards B. Performance Standards C. Learning Competencies / Objectives (Write the LC code for each) II. CONTENT III. LEARNINGRESOURCES A. References Teacher’s Guide pages 2. Learner’s Materials pages 3. Textbook pages 4. Additional Materials for Learning B. Other Learning Resources The learner demonstrates understanding of key concepts of normal probability distribution. The learner is able to accurately formulate and solve real-life problems in different disciplines involving normal distribution. The learner identifies regions under the normal curve corresponding to different standard normal values. (M11/12SP-IIIc-3) Specific Objectives: The learner will be able to: Read and utilize the z- table correctly. Draw a sketch of a normal curve Identify regions under the normal curve corresponding to different standard normal values. Regions under the Normal Curve Next Century Mathematics (Statistics and Probability) Senior High School by Jesus P. Mercado pages 308-321 Statistics and Probability by Rene R. Belecina et. Al. First Edition https://int.search.myway.com/search/AJimage.j html?&n=7858e4f9&p2=%5E0D%5Exdm495% 5ETTAB03%5Eph&pg=AJimage&pn=4&ptb=2E 73C0C4-6C67-4509-B7E8BCE1002E511C&qs=&searchfor=normal+distri bution+curve&si=61279913649036127991365303&ss=sub&st=tab&tpr=jrel2&trs= wtt&ots=1570210308912&imgs=1p&filter=on&i mgDetail=true IV. PROCEDURES Reviewing previous I. Ask the leader of the day to do the routinely activities: lesson or lead the prayer presenting the new do the head counting lesson recapitulation of the previous lesson 29 (the teacher thank the leader of the day’s effort) II. Ask the students to recall the definition of the standard normal curve (A standard normal curve is a normal probability distribution that has a mean (μ) equals 0 and a standard deviation (σ) equals 1) *the teacher may present the concept on the board or any visual aid he/ she may have then show them a picture or an example of a normal curve with the properties of a normal distribution / curve. Establishing a purpose for the lesson Presenting examples/ instances of the new lesson I. Discussing new concepts and practicing new skills #1 A. The teacher would say: “Today we are guided by the following objectives … “ The teacher presents a power point (any visual) of the objectives of the lesson. B. (The presentation of today’s rule during class discussion is encouraged if any) A. Let them recall the role of the standard deviation in the normal curve. (the distance or units at the bottom part of the curve is the standard deviation σ) B. The teacher presents the normal curve divided in desired portions. *through this, the teacher can give preview of the lesson about the regions under the normal curve. The teacher present the video on “Normal Distribution Table - Z-table Introduction” Ask the students to perform the activity. (to check their skill on the utilization of the z- table) By triad: Give the corresponding area between z= 0 and each of the following: (Check the answer after 5 minutes) P(z=0.23) answer : 0.0910 P(z=1.09) answer: 0.3621 P(z=2.01) answer: 0.4778 P(z=-0.98) answer: 0.3365 P(z=-0.03) answer: 0. 0120 The teacher shall do the corrections/ fixing of the mistakes committed by the students in the utilization of the z- table. The teacher has to inform the students of the other possible z- 30 table. (the teacher can present the different ztable trough a power point presentation) Discussing new concepts and practicing new skills #2 A. The teacher shall discuss the proportions of areas under the normal curve through a video presentation on “ Normal Distribution Explained Simply (part 1)” and “b Normal Distribution - Explained Simply (part 2)” B. GROUP ACTIVITY In a group of 5 students, the teacher asks the students to give their ideas of the following statement ask them to support their answers illustrating each situation in a normal curve: (answer can be written in a manila paper or through a PPT. The students have to identify the correct statement base on the equivalent proportions of areas under the normal curve). 1. Z – score -2 and 2 covers 95.44% 2. The area from z- score 1 to 2 is 15%. 3. The total area between z= -1 and z= +1 is 0.6826 Answers: 1. The statement is correct or true by adding the values from the table P(Z=2)=0.4772 or 47.72% and P(Z=-2)=0.4772 or 47.72% the sum is 0.9544 or 95.44%. 2. The area covered from z= 0 to z=+1 is 0.3413 or 34.13% and from z=0 to z= +2 is 0.4772 0r 47.72% then the difference of the values is 0.1359 or 13.59% not 15%. Therefore, the statement is incorrect or false. 3. The sum of the values from z= 0 to z= -1 which is 0.3413 and from z= 0 to z=+1 which is 0.3413, is 0.6826. So, the statement is true or correct. 31 *the teacher should give the correct illustration of each statement as she/ he checks and explains the answers (the teacher can use a ppt or an IM for normal curve) **ICT INTEGRATION If computers are available, show learners that we could alternatively use Excel to obtain (a) and (b). Merely enter the command = NORMSINV(0.5832) and generate the value of z as 0.210086 for (a). While for (b), we enter the command = NORMSINV(1-0.8508) and thus find z as –1.03987. * the teacher can explore some z- scores for further drills on the ICT integration. A. Developing mastery (Leads to Formative Assessment 3) B. Finding practical applications of concepts and skills in daily living C. Making generalizations and abstractions about the lesson D. Evaluating Learning V. Let the students perform the activity on the areas under the normal curve. (see attached sheet 1) ; (different colors can be use if desired) Ask the students to give their real- life examples of having regions or areas or a figure parallel or related to the lesson. (example: covered area in cleaning the floor/ applying floor wax in an specific area / region of the floor) * Creativity and imaginative skill of the teacher is highly encouraged. Present the normal curve with the common / usual proportions under the normal curve. Let the students give at least 1 visible proportions of the areas under the normal curve. Let the students perform attached sheet 2 REMARKS VI. REFLECTION A. No. of learners who earned 80% in the evaluation. B. No. of learners who require additional activities for remediation who scored below 80%. 32 C. Did the remedial lessons work? No. of learners who have caught up with the lesson. D. No. of learners who continue to require remediation E. Which of my teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/discover which I wish to share with other teachers? 33 Sheet 1 Shade the normal curves with its given corresponding z- score then identify the proportions of areas under the normal curve. Greater than z= 1.065 Between z= -2. 08 and z= 0.78. Between z= 0. 12 and z= 1.96 P(-1.53 < 0.45) From mean (μ) to z= 2.05 Between z=-1.12 and z= 1.12 34 Sheet 2 EVALUATION A. Determine the proportions of the areas under the following normal curves. 1. 2. -2 1 -1 3. 1 2 4. -2 -0.64 -2 -1 B. Illustrate and give the proportions of the regions under the normal curve with the following z- scores. 5. 𝑧 = 0.38 ; 𝑓𝑟𝑜𝑚 𝑧 = 0 6. 𝑧 = −1.29 ; 𝑓𝑟𝑜𝑚 𝑧 = 0 7. 𝑏𝑒𝑡𝑤𝑒𝑒𝑛 𝑧 = 2.01 𝑎𝑛𝑑 𝑧 = 2.93 −0.67 8. 𝑔𝑟𝑒𝑎𝑡𝑒𝑟 𝑡ℎ𝑎𝑛 𝑧 = 9. 𝑏𝑒𝑙𝑜𝑤 𝑧 = 1.37 10. 𝑡ℎ𝑒 𝑟𝑖𝑔ℎ𝑡 𝑜𝑓 𝑧 = 2.03 35 2 2.5 2 School Grade Level Learning Area Quarter Teacher Time & Date Eleven Statistics and Probability Third Quarter I. OBJECTIVES A. Content Standards B. Performance Standards C. Learning Competencies / Objectives (Write the LC code for each) II. CONTENT III. LEARNINGRESOURCES A. References Teacher’s Guide pages 2. Learner’s Materials pages 3. Textbook pages The learner demonstrates understanding of key concepts of normal probability distribution. The learner is able to accurately formulate and solve real-life problems in different disciplines involving normal distribution. The learner converts a normal random variable to a standard normal variable and vice versa. (M11/12SP-IIIc-4) Specific Objectives: The learner will be able to: 1. Find the z- value that corresponds to a score X 2. Utilize/ use z- table independently and correctly. 3. Convert a normal random variable to a standard normal variable and vice versa 4. Sketch the normal curve with convert a normal random variable to a standard normal variable and vice versa Conversion of a normal random variable to a standard normal variable and vice versa Next Century Mathematics (Statistics and Probability) Senior High School by Jesus P. Mercado pages 308321 Statistics and Probability by Rene R. Belecina et. Al. First Edition 4. Additional Materials for Learning B. Other Learning Resources IV. PROCEDURES Reviewing I. Ask the leader of the day to do the routinely activities: previous lesson or lead the prayer presenting the new do the head counting lesson recapitulation of the previous lesson (the teacher thank the leader of the day’s effort) 36 II. Ask the students to recall the properties of a normal curve/ distribution through the activity: A. Sketch the normal curve with the following properties 1. μ= 0, σ=1 2. μ= 35, σ=3 3. μ=98, σ= 2.5 4. μ=105, σ= 4 5. μ= 100, σ= 20 *the teacher shall focus on the baseline of the normal curve and the standard deviation. The distance of each unit should be reviewed. Establishing a purpose for the lesson A. The teacher presents the objectives of the lesson through a power point presentation. B. The teacher presents a normal curve with the converted raw scores. Let the students determine the μ and σ. Presenting examples/ instances of the new lesson A. Let them recall the role of the standard deviation in the normal curve. (the distance or units at the bottom part of the curve is the standard deviation σ) J. Discussing The teacher presents the video on the derivation of new concepts the formula and practicing new skills #1 The areas under the normal curve are given in terms of z- values or scores. Either the z- score locates X within a sample or within a population. The formula for calculating z is : For population data For sample data 𝑋−𝜇 𝑧= 𝜎 Where : X- given measurement μ- population mean σ- population standard deviation 37 𝑧= 𝑋 − 𝑋̅ 𝑠 s- sample standard deviation X- sample mean Discussing new concepts and practicing new skills #2 *raw scores may be composed of large values, but large values cannot be accommodated at the base line of the normal curve. So, they need to be converted into scores for convenience without sacrificing the meaning associated to the raw score. A. Group Activity: Solve for the equivalent z- score of the problem assigned to your group, then sketch the normal curve showing the calculated z- score that corresponds to the raw score X. Group 1- Given the mean μ= 60 and the standard deviation σ= 5 of a population, find the z- value that corresponds to score X= 54. Group 2- Given the mean μ= 78 and the standard deviation σ= 13 of a population, find the z- value that corresponds to score X= 88. Group 3- Given the mean μ= 45 and the standard deviation σ= 3 of a population, find the z- value that corresponds to score X= 40. Group 4- Given the mean μ= 128 and the standard deviation σ= 2.6 of a population, find the z- value that corresponds to score X= 131. Group 5- Given the mean μ= 155 and the standard deviation σ= 6.5 of a population, find the z- value that corresponds to score X= 147.5. B. Let them present their output through a manipulative normal curve made – up of cardboard. *The teacher can make her/ his own rubrics according to the ability of the students. *the teacher should give the correct illustration of each statement as she/ he checks and explains the answers (the teacher can use a ppt or an IM for normal curve) E. Developing mastery (Leads to Formative Assessment 3) A. By triad. : Give the missing value; 1. 2. 3. 4. 5. B. X= 23, μ=32, σ=8, z=? μ=231, σ= 120, X= 250, z=? μ=127, σ= 5, X= 98, z=? μ=450, σ= 15, z=-1.5, X=? σ= 5, X= 98, z=2.21, μ=? Checking of the answer may be done through a quick check where the teacher will give the answers or if the students seem to be slow in understanding the concept, the solution of each problem shall be presented. 38 F. Finding Ask the students to give their real- life examples of practical having small or large things which need to be converted applications just to fit in an actual scenario of concepts * Creativity and imaginative skill of the teacher is highly and skills in encouraged. daily living G. Making Ask the students to give the summary of the generalization lesson. s and abstractions The teacher shall present the formulae to the students about the through a PPT. lesson The formula for calculating z is : For population data For sample data 𝑋−𝜇 𝑧= 𝜎 𝑧= Where : X- given measurement μ- population mean σ- population standard deviation s- sample standard deviation X- sample mean H. Evaluating Learning Let the students perform attached sheet 1 V. REMARKS VI. REFLECTION A. No. of learners who earned 80% in the evaluation. B. No. of learners who require additional activities for remediation who scored below 80%. C. Did the remedial lessons work? No. of learners who have caught up with the lesson. D. No. of learners who continue to require remediation E. Which of my teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal or supervisor can help me solve? 39 𝑋 − 𝑋̅ 𝑠 G. What innovation or localized materials did I use/discover which I wish to share with other teachers? EVALUATION Shade the normal curves with its corresponding z- score after converting the raw score to its standard normal variable. X= 69 μ=75 σ= 14 z=? X= 219 μ=200 σ=21 z=? X= 950 μ=1000 σ=25 z=? X= 12 μ=20 σ=6.5 z=? Solve for the missing value. X= 250 σ=15.5 z=1.65 μ=? 40 X= 100 z=-0.98 μ= 112 σ=? School Grade Level Learning Area Quarter Teacher Time & Date Eleven Statistics and Probability Third Quarter I. OBJECTIVES The learner demonstrates understanding of key concepts of normal probability distribution. The learner is able to accurately formulate and solve B. Performance Standards real-life problems in different disciplines involving normal distribution. The learner computes probabilities and percentiles using the standard normal table. (M11/12SP-IIIc-d1) C. Learning Specific Objectives: The learner will be able to: Competencies / 5. Recall the concept on the reading of Objectives probabilities on the z- table. (Write the LC code for 6. Find the z- scores when probabilities are each) given. 7. Computes the probabilities and percentiles using the standard normal table. A. Content Standards II. CONTENT Locating Percentiles Under the Normal Curve III. LEARNINGRESOURCES A. References Teacher’s Guide pages 2. Learner’s Materials pages 3. Textbook pages 4. Additional Materials for Learning B. Other Learning Resources Next Century Mathematics (Statistics and Probability) Senior High School by Jesus P. Mercado pages 308-321 Statistics and Probability by Rene R. Belecina et. Al. First Edition a. https://www.google.com/search?q=percentile &oq=percentile&aqs=chrome..69i57j0l5.2828j 0j9&sourceid=chrome&ie=UTF-8 b. IV. PROCEDURES A. Reviewing previous lesson or presenting the new lesson I. Ask the leader of the day to do the routinely activities: lead the prayer do the head counting recapitulation of the previous lesson 41 (the teacher thank the leader of the day’s effort) II. Ask the students to recall the process on how to read values from the z- table by asking the students to give the equivalent probability of the following; (this can be a quiz bee with the help of the power point) 1. z= 0.12 2. z=-2.13 3. z=1.28 4. z=2.48 5. z=-0.87 6. z=-1.24 7. z= -2.09 8. z= 2.01 9. z= 1.72 10. z= 0.04 B. Establishing a purpose for the lesson C. Presenting examples/ instances of the new lesson D. Discussing new concepts and practicing new skills #1 C. The teacher presents the objectives of the lesson through a power point presentation. D. The teacher ask: “Which of the following are familiar to you?” a. First Honor b. Top five c. Eliminated candidates are the below 10% d. Scholars are the top two e. Remediation session is for students at the bottom 5. *the teacher shall ask the students to give the meaning of each situation above. A. (optional) the teacher can make a huge normal curve and ask the students to stand on the position of the following:(this can be done by group) 1. Above z= 2.00 2. Below z = 0.08 3. More than z= 1.54 4. Less than or equal to z=-1.34 5. To the right of z= 0.49 The teacher presents and asks the opinion of the class about the picture. 42 *the idea of the percentile shall be given emphasis and be defined. Percentile - each of the 100 equal groups into which a population can be divided according to the distribution of values of a particular variable. A percentile is a measure used in statistics indicating the value below which a given percentage of observations in a group of observations fall E. Discussing new concepts C. The teacher shall present the following and practicing new skills #2 considerations or important things to remember when we are given probabilities and we know their corresponding z- scores. 1. A probability value corresponds to an area under the normal curve. 2. In the Table of Areas Under the Normal Curve, the numbers in the extreme left and across the top are z- scores, which are the distances along the horizontal scale. The numbers in the body of the table are areas or probabilities. 3. The z- scores to the left of the mean are negative values. D. Group Activity: Ask the students to sketch the following: Group 1: P25 Group 2: P65 Group 3: P88 Group 4: P90 Group 5: P98 E. Let them give the meaning of the assigned percentile to their group. F. Ask them to present the illustrations(for the wrong sketch the teacher should check or correct the illustration) G. Discussion of how to determine the z- score of every percentile. The 95th percentile is z= 1.645 .95/2 = 0.45 where there is no exact 0.45 in the table so therefore we get the nearest values z=1.65 (0.4505) and the z= 1.64 (0.4495) by interpolation the value now is z= 1.645. H. Ask the students to give the z – score of their assigned percentile as stated above (B) F. Developing mastery (Leads to Formative Assessment 3) A. Let them perform the activity by pair: 1. Find the upper 10% of the normal curve. Illustrate the normal curve. 43 2. The results of a nationwide aptitude test in Mathematics are normally distributed with m=80 and s= 15. What is the percentile rank of a score 84? I. Check their answer and resolve the misconceptions committed by the students. G. Finding practical applications of concepts and skills in daily living H. Making generalizations and abstractions about the lesson I. Evaluating Learning Ask them to give their own example of the percentile rank (students can mention their rank after taking the quiz or any test they had) Is a normal curve useful in visualizing the positions of the scores or the rank? Why do you think so? Write your thoughts in a piece of paper. Let the students perform attached sheet 1 V. REMARKS VI. REFLECTION A. No. of learners who earned 80% in the evaluation. B. No. of learners who require additional activities for remediation who scored below 80%. C. Did the remedial lessons work? No. of learners who have caught up with the lesson. D. No. of learners who continue to require remediation E. Which of my teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/discover which I wish to share with other teachers? 44 EVALUATION 1. Sketch the 85th percentile. 2. Present the procedure in calculating the P99 of the normal curve then draw. 3. What is the percentile rank of a score of 56 from the normally distributed NAT results with mean of 75 and σ= 20. Draw. 45 School Grade Level Learning Area Quarter Teacher Time & Date Eleven Statistics and Probability Third Quarter I. OBJECTIVES A. Content The learner demonstrates understanding of key concepts of Standard sampling ad sampling distributions of the sample mean. B. Performance Standard The learner is able to apply suitable sampling and sampling distributions of the sample mean to solve real-life problems in different disciplines. C. Learning Competency/Obj ectives The learner illustrates random sampling. M11/12SP-IIId-2. II. CONTENT Random Sampling III. LEARNING RESOURCE References 1. Jose Dilao S., Orines F and Bernabe J. (2009). Advanced Algebra, Trigonometry and Statistics. SD Publications, Inc. pp 234-236. 2. Ocampo J. & Marquez W. (2016). Senior High Conceptual Math and Beyond Statistics and Probability. Brilliant Creations Publishing, Inc. pp.86-93. Other Learning https://www.youtube.com/watch?v=xh4zxC1OpiA Resource IV. PROCEDURES A. Reviewing Recall from our study of probability that the number of previous lessons combinations of n objects taken r at a time is obtained by or presenting the using the formula. new lesson 𝑛! C (n, r) = (𝑛−𝑟)!𝑟! 𝑤ℎ𝑒𝑟𝑒 𝑛 ≥ 𝑟 Evaluate the following: 1.C (5, 3) 2. C (10, 4) 3. C (9, 6) 4. C (8, 2) 5. C (7, 6) B. Establishing a purpose for the lesson The students will explain their solutions. To prepare the students in the lesson, activities are as follows: A.A sample of investment experts was asked to give their opinion as to where they would invest their money. The following are their responses. Stocks Real estate Real estate Precious metals Art Precious metals Real state Precious metals Commodities Art Precious metals Foreign money 46 Precious metals Stocks Stocks Real estate Commodities Stocks Real estate Commodities Commodities Foreign money Stocks Stocks Real estate Stocks Real estate Stocks Real estate Precious metals Real estate Real estate Foreign money Construct a table to show the frequency distribution of the given responses. Types of Investment C. Presenting Examples/Instan ces of the Lesson Frequency Norma wants to know the common number of children her classmates’ families have. Which of the following samples is a good representation of the class? Why? 1.A sample consisting of Norma’s friends 2.A sample consisting of students belonging to rich families. 3. A sample consisting of students whose names were drawn from a box all the names of students in Norma’s class. Wrong conclusion may be inferred from samples given in numbers 1 and 2. This sample will not represent the correct number of children the families of Norma’s classmates have. The sample in a number 3 in the best representation of the class. This is idea of representativeness leads to the importance of random sampling, a method of drawing out a sample from a population without a definite plan, purpose, or pattern. D. Discussing New concepts and Practicing New Skills # 1 E. Developing Mastery Let students analyze the video in the https://www.youtube.com/watch?v=xh4zxC1OpiA link- After watching the video presentation, the students will define random sampling and state its uses. Group activity for 10 minutes. The students are task to: 1. Create problem that involves random sampling. 2. Construct a table that show frequency distribution of the samples. 3. What learning discovered in doing such activity? Would you be able to use this in your life? How and why? 47 The rubrics will be used in scoring the performance of the group. Categor 4 3 2 1 ies Excellen Satisfact Developi Beginning t ory ng Mathe Demons Demons Demonstr Shows lack matical trates a trates a ates of Concep thoroug satisfact incomplet understandin t h ory e g and have underst underst understa severe anding anding nding misconceptio of the of the and has ns. topic uses it some and to misconce uses it simplify ptions. accurate the ly to problem solve . the problem Accura All The Generally Errors in cy of computa computa , most of computations comput tion are tion are the are severe. ation. correct correct. computati an are ons are logically not present correct. ed Organiz Highly Satisfact Somewh Illogical and ation of organize orily at obscure. No the d, flows organize cluttered. logical report smoothl d. Flow is connections y, and Sentenc not of ideas. observe e flow is consisten Difficult to s logical generall tly determine connecti y smooth, the meaning. ons of smooth appears points. and disjointed logical. . Particip ation of the membe rs All member s take part in the activity, support and encoura ge others in the group member 48 Almost 90-99% take part in the activity, support and encoura ge others in the group member Almost 80-89% take part in the activity, support and encourag e others in the group members do not find fault Almost 7079% take part in the activity, support and encourage others in the group. There isa conflict relationship in doing the activity. F. Making generalization and abstraction about the lesson G. Evaluating Learning s do not s do not in one find fault find fault another, in one in one open to another, another, comment open to open to s and commen commen criticism. ts and ts and criticism criticism . . What is random sampling? Random sampling is a method by which every element of a population has a chance of being included in a sample. That is, the elements that compose the sample are taken without purpose. The more elements in the sample, the better the chances of getting a true picture of the whole population. Determine whether the following is a random sample or not. Explain your answer. 1.To select the students to attend the summer workshop in Sorsogon, the teacher told her class to count off, and then selected those even-numbered students for the workshop. 2. To study the average number of years a family has stayed in Barangay Guinlajon, the barangay captain chose to interview the families around his residence. 3. To find the average number of dengue victims in hospitals per day, a researcher made a list of all hospitals in Sorsogon Province, and then selected every fifth in the list. 4. A survey of the prevailing cost of rice was undertaken in the seven key cities of the country. 5. To select students for MTAP competition, the school math coordinator decided to screen competitive students from junior high school. V. REMARKS VI. REFLECTION A. No. of learners who earned 80% in the evaluation. B. No. of learners who require additional activities for remediation who scored below 80%. C. Did the remedial lessons work? No. of learners who have caught up with the lesson. D. No. of learners who continue to require remediation 49 E. Which of my teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/discover which I wish to share with other teachers? 50 School Grade Level Learning Area Quarter Teacher Time & Date Eleven Statistics and Probability Third Quarter I. OBJECTIVES A. Content The learner demonstrates understanding of key concepts of Standard sampling ad sampling distributions of the sample mean. B. Performance Standard The learner is able to apply suitable sampling and sampling distributions of the sample mean to solve real-life problems in different disciplines. C. Learning Competency/ Objectives The learner distinguishes between parameter and statistic. M11/12SP-IIId-3. II. CONTENT Parameter and Statistic III. LEARNING RESOURCE References 3. Ocampo J. & Marquez W. (2016). Senior High Conceptual Math and Beyond Statistics and Probability. Brilliant Creations Publishing, Inc. pp.86-93. 2. Supplementary Statistics Topics. Retrieved from https://www2.southeastern.edu/Academics/Faculty/dgurne y/Math241/StatTopics.html 5. Surbhi (2017). Difference Between Statistic and Parameter Retrieved from https://keydifferences.com/differencebetween-statistic-and-parameter.html Other Learning https://www.youtube.com/watch?v=M-L8C2aOf7E Resource IV. PROCEDURES A. Reviewing Jumble the letters that corresponds to the given definition. previous 1. AATD- facts and statistics collected together for reference or lessons or analysis. presenting the 2. NIOTALUPOP- an aggregate observation of subjects new lesson grouped together by a common feature 3. ELPMSA- a small part or quantity intended to show what the whole is like. 4.UAIESMMRZ- give a brief statement of the main points of (something). 5. PRMTRSAAEE- a numerical or other measurable factor forming one of a set that defines a system or sets the conditions of its operation. B. Establishing a purpose for the lesson Let students analyze the given definition and comparison chart of statistic and parameter In statistics vocabulary, we often deal with the terms parameter and statistic, which play a vital role in the determination of the sample size. Parameter implies a summary description of the characteristics of the target population. On the other extreme, 51 the statistic is a summary value of a small group of population i.e. sample. -Definition of Statistic A statistic is defined as a numerical value, which is obtained from a sample of data. It is a descriptive statistical measure and function of sample observation. A sample is described as a fraction of the population, which represents the entire population in all its characteristics. The common use of statistic is to estimate a particular population parameter. From the given population, it is possible to draw multiple samples, and the result (statistic) obtained from different samples will vary, which depends on the samples. -Definition of Parameter A fixed characteristic of population based on all the elements of the population is termed as the parameter. Here population refers to an aggregate of all units under consideration, which share common characteristics. It is a numerical value that remains unchanged, as every member of the population is surveyed to know the parameter. It indicates true value, which is obtained after the census is conducted C. Presenting Examples/Inst ances of the Lesson The students will distinguish the parameter and statistic in the given statements. 1.A researcher wants to know the average weight of females aged 22 years or older in Sorsogon. The researcher obtains the average weight of 54 kg, from a random sample of 40 females. -Solution: In the given situation, the statistics are the average weight of 54 kg, calculated from a simple random sample of 40 females, in Sorsogon while the parameter is the mean weight of all females aged 22 years or older. 2.A researcher wants to estimate the average amount of water consumed by male teenagers in a day. From a simple random sample of 55 male teens the researcher obtains an average of 1.5 litres of water. 52 -Solution: In this question, the parameter is the average amount of water consumed by all male teenagers, in a day whereas the statistic is the average 1.5 litres of water consumed in a day by male teens, obtained from a simple random sample of 55 male teens D. Discussing New concepts and Practicing New Skills # 1 E. Developing Mastery Let the students analyze the video in https://www.youtube.com/watch?v=M-L8C2aOf7E the link- After watching the video presentation, the students will reflect to the difference between parameter and statistic and connect it to real life. Group activity for 10 minutes. The students are task to: 4. Create statements that involves parameter and statistic. 5. What learning discovery did you found useful in your daily life activities? The rubrics will be used in scoring the performance of the group. Categories 4 Excellent 3 Satisfactory 2 Developing 1 Beginning Mathem atical Concept Demonstr ates a thorough understa nding of the topic and uses it accuratel y to solve the problem All computati on are correct an are logically presente d Highly organize d, flows smoothly, and observes logical connectio ns of points. Demonstr ates a satisfacto ry understa nding of the uses it to simplify the problem. Demonstra tes incomplete understan ding and has some misconcep tions. Shows lack of understan ding and have severe misconcep tions. The computati on are correct. Generally, most of the computatio ns are not correct. Errors in computatio ns are severe. Satisfact orily organize d. Sentence flow is generally smooth and logical. Somewhat cluttered. Flow is not consistentl y smooth, appears disjointed. Illogical and obscure. No logical connection s of ideas. Difficult to determine the meaning. Accurac y of computa tion. Organiza tion of the report 53 Participa tion of the member s All members take part in the activity, support and encourag e others in the group members do not find fault in one another, open to comment s and criticism. Almost 90-99% take part in the activity, support and encourag e others in the group members do not find fault in one another, open to comment s and criticism. Almost 8089% take part in the activity, support and encourage others in the group members do not find fault in one another, open to comments and criticism. Almost 7079% take part in the activity, support and encourage others in the group. There isa conflict relationshi p in doing the activity. F. Making generalization and abstraction about the lesson Differentiate parameter to statistic. G. Evaluating Learning Problems (1) through (6) below each present a statistical study*. For each study, identify both the parameter and the statistic in the study. -Parameters are numbers that summarize data for an entire population. Statistics are numbers that summarize data from a sample, i.e. some subset of the entire population 1) A researcher wants to estimate the average height of women aged 20 years or older. From a simple random sample of 45 women, the researcher obtains a sample mean height of 63.9 inches. 2) A nutritionist wants to estimate the mean amount of sodium consumed by children under the age of 10. From a random sample of 75 children under the age of 10, the nutritionist obtains a sample mean of 2993 milligrams of sodium consumed. 3) Nexium is a drug that can be used to reduce the acid produced by the body and heal damage to the esophagus. A researcher wants to estimate the proportion of patients taking Nexium that are healed within 8 weeks. A random sample of 224 patients suffering from acid reflux disease is obtained, and 213 of those patients were healed after 8 weeks. 4) A researcher wants to estimate the average farm size in Kansas. From a simple random sample of 40 farms, the researcher obtains a sample mean farm size of 731 acres. 54 5) An energy official wants to estimate the average oil output per well in the United States. From a random sample of 50 wells throughout the United States, the official obtains a sample mean of 10.7 barrels per day. 6) An education official wants to estimate the proportion of adults aged 18 or older who had read at least one book during the previous year. A random sample of 1006 adults aged 18 or older is obtained, and 835 of those adults had read at least one book during the previous year. J. Additional activities for application or remediation V. REMARKS VI. REFLECTION A. No. of learners who earned 80% in the evaluation. B. No. of learners who require additional activities for remediation who scored below 80%. C. Did the remedial lessons work? No. of learners who have caught up with the lesson. D. No. of learners who continue to require remediation E. Which of my teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal or 55 supervisor can help me solve? G. What innovation or localized materials did I use/discover which I wish to share with other teachers? 56 School Grade Level Learning Area Quarter Teacher Time & Date Eleven Statistics and Probability Third Quarter I. OBJECTIVES A. Content The learner demonstrates understanding of key concepts of Standard sampling ad sampling distributions of the sample mean. B. Performance Standard The learner is able to apply suitable sampling and sampling distributions of the sample mean to solve real-life problems in different disciplines. C. Learning Competency/O bjectives M11/12SP-IIId-4. The learner identifies distributions of statistics (sample mean) II. sampling CONTENT Identifying Sampling Distributions of statistics (sample mean) III. LEARNING RESOURCE References Ocampo J. & Marquez W. (2016). Senior High Conceptual Math and Beyond Statistics and Probability. Brilliant Creations Publishing, Inc. pp.86-93. Other Learning https://www.youtube.com/watch?v=xh4zxC1OpiA Resource IV. PROCEDURES A. Reviewing Find the mean of the following sets of data. previous Set of data Mean lessons or 1.18, 19, 20, 21, 22,21, 20, 19, 17, 17, 16, 16, 16 presenting the 2.5,3,6,9, 7,2,10,8 new lesson 3.18,16,19,22,20, 15,23,21,21 4.76,69,63,82,29,83,64,71,76 5.36,37,37,38,23,30,35 B. Establishing a purpose for the lesson C. Presenting Examples/Insta nces of the Lesson Suppose we have a population of size N with a mean 𝜇, and we draw or select all possible samples of size n from this population. Naturally, we expect to get different values of the means for each sample. The sample means may be less than, greater than, or equal to the population mean 𝜇. The sample means obtained will from a frequency and the corresponding probability distribution can be constructed. This distribution is called the sampling distribution of the sample means. How do we construct the sampling distribution of the sample means? Study the given example. A population consists of five values (Php2, Php 3, Php 4, Php 5, Php6). A sample of size 2 is to be taken from this population. a. How many samples are possible? List them and compute the mean of each sample. 57 D. Discussing New concepts and Practicing New Skills # 1 E. Developing Mastery b. Construct the histogram of the sampling distribution of the sample means. The following table gives the monthly salaries Officer Salary A 8 B 12 C 16 D 20 E 24 F 28 1.How many samples are possible? List them and compute the mean of each sample? 2. Construct the sampling distribution of the sample means. 3. Construct the histogram of the sampling distribution of the sample means. Group activity for 10 minutes. The students are task to: 1. Create problem that involves sampling distributions of statistics (sample mean). 2. Construct sampling distribution and histogram of the sample means 3. What learning discovered in doing such activity? Would you be able to use this in your life? How and why? The rubrics will be used in scoring the performance of the group. Categories 4 Excellent 3 Satisfactory 2 Developing 1 Beginning Mathe matical Concep t Demons trates a thoroug h underst anding of the topic and uses it accurate ly to solve the problem All computa tion are correct an are logically present ed Demons trates a satisfact ory underst anding of the uses it to simplify the problem . Demonstr ates incomplet e understa nding and has some misconce ptions. Shows lack of understandin g and have severe misconceptio ns. The computa tion are correct. Generally Errors in , most of computations the are severe. computati ons are not correct. Accura cy of comput ation. 58 Organiz ation of the report Highly organize d, flows smoothl y, and observe s logical connecti ons of points. Satisfact orily organize d. Sentenc e flow is generall y smooth and logical. Somewh at cluttered. Flow is not consisten tly smooth, appears disjointed . Illogical and obscure. No logical connections of ideas. Difficult to determine the meaning. Particip ation of the membe rs F. Making generalization and abstraction about the lesson G. Evaluating Learning All Almost Almost Almost 70member 90-99% 80-89% 79% take s take take take part part in the part in part in in the activity, the the activity, support and activity, activity, support encourage support support and others in the and and encourag group. There encoura encoura e others isa conflict ge ge in the relationship others in others in group in doing the the the members activity. group group do not member member find fault s do not s do not in one find fault find fault another, in one in one open to another, another, comment open to open to s and commen commen criticism. ts and ts and criticism criticism . . What is sampling distribution of sample means? -It is the frequency distribution of the sample means taken from a population. A. Determine the number of different samples of the given size n that can be drawn from the given population of size N. N N Number of Possible Samples 7 3 15 5 50 4 10 3 25 4 B. Random samples of size n=2 are drawn from a finite population consisting of numbers 5, 6,7,8,and 9. a. How many possible samples are there? 59 b .List all the possible samples and the corresponding mean for each sample. c. Construct the sampling distribution of the sample means. d. Construct the histogram for the sampling distribution of the sample means. Describe the shape of the histogram. V. REMARKS VI. REFLECTION A. No. of learners who earned 80% in the evaluation. B. No. of learners who require additional activities for remediation who scored below 80%. C. Did the remedial lessons work? No. of learners who have caught up with the lesson. D. No. of learners who continue to require remediation E. Which of my teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/discover which I wish to share with other teachers? 60 School Grade Level Learning Area Quarter Teacher Time & Date I. OBJECTIVES A. Content Standard B. Performance Standard C. Learning Competency/Objectives Write the LC code for each I.CONTENT II.LEARNING RESOURCES A. Reference 1.Teacher’s Guide pages 2.Learner’s Material pages 3.Textbook pages 4.Additional Materials from Learning Resource(LR) Portal B. Other Learning Resources IV. PROCEDURES A. Reviewing previous lesson or presenting the new lesson Eleven Statistics and Probability Third Quarter The learner demonstrates understanding of key concepts of sampling and sampling distributions of the sample mean. The learner is able to apply suitable sampling and sampling distributions of the sample mean to solve real-life problems in different disciplines. The learners shall be able to finds the mean, variance and the standard deviation of the sampling distribution of the sample mean. M11/12SP-IIId-5 Sampling and Sampling Distributions K-12 Curriculum Guide Statistics and Probability by Belencina, Baccay & Mateo pp. 110-119 Calculator, manila paper, pentel pen, projector and laptop Tell the class that the sampling distribution of the sample means is actually the probability distribution of the sample mean Start the lesson with a review on how to construct the sampling distribution of the sample mean. Consider a population consisting of 1,2,3,4 and 5. Suppose sample size 2 are drawn from this population Construct the sampling distribution of the sample mean. 61 Step 1:Determine the number of possible samples that can be drawn from the population using the combination formula 5! 5𝐶2 = (5−2)!2! 5𝑥4𝑥3! = 3!2! = 20/2 5𝐶2 = 10 𝑛! n𝐶𝑟 = (𝑛−𝑟)!𝑟! Step 2:List all possible samples and compute the mean of each sample Or through the use of scientific Calculator Keystroke: 5 Sample Mean Step 3: Construct a frequency distribution of the sample means obtained in step 2 Sam Frequ ple ency Mea n 𝑥̅ Proba bility P(x) Tot al 62 n𝐶𝑟 Sample 1,2 1,3 1,4 1,5 2,3 2,4 2,5 3,4 3,5 4,5 2 = Display Mean 1.50 2.00 2.50 3.00 2.50 3.00 3.50 3.50 4.00 4.50 Sample Frequency Probability Mean P(x) 𝑥̅ 1.50 1 1/10 2.00 1 1/10 2.50 2 2/10 or 1/5 2 2/10 or 1/5 3.50 2 2/10 or 1/5 4.00 1 1/10 4.50 1 1/10 Total 10 1.00 B. Establishing a purpose for the lesson Tell the class that on this lesson we shall continue to compute the mean and variance of the sampling distribution of the sample mean C. Presenting examples/instances of the new lesson Consider a population consisting of 1,2,3,4 and 5. Suppose sample size 2 are drawn from this population 𝜇= Σ𝑥 𝑛 1+2+3+4+5 5 𝜇= 𝜇=3.00 Compute the population mean from the given example D. Discussing new concepts and practicing new skills # 1 Challenge the students to compare this mean to the mean of the sampling distribution of the sample mean after the next activity had been done. Discuss the steps on how to find the mean and variance of the given sampling distribution (PPT) ICT Integration Activity 2 Consider a population consisting of 1,2,3,4 and 5. Suppose sample size 2 are drawn from this population Find the mean and variance of the sampling distribution of the sample mean? Remind the students to follow the s 1. Construct the sampling distribution of the sample mean. 2. Compute the mean of the sampling distribution of the sample mean (𝜇𝑥̅ 63 Answers: 𝑋̅ P(𝑋̅) 1.50 2.00 2.50 3.00 3.50 4.00 4.50 Total 1/10 1/10 1/5 1/5 1/5 1/10 1/10 1.00 𝑋̅ ∙ P(𝑋̅) 0.15 0.20 0.50 0.60 0.70 0.40 0.45 ̅ ̅ )= 𝚺𝑿 ∙ P(𝑿 3.00 ̅) ̅ ∙ P(𝑿 𝜇𝑥̅ = 𝚺𝑿 𝜇𝑥̅ = 3.00 mean of the sampling distribution of the means by multiplying the sample mean by the corresponding probability and add the results. 3. Compute the variance (𝜎 2 𝑥̅ ) of the sampling distribution of the sample Mean using the formula 𝜎 2 𝑥̅ = Σ P(𝑋̅) ∙ (𝑋̅ 2 – 𝜇) 4. Compute the standard deviation by finding the square root of the variance 𝜎𝑥̅ = √Σ P(𝑋̅) ∙ (𝑋̅ – 𝜇)2 Complete the table below 𝑋̅ P 𝑋̅ (𝑋̅ P(𝑋̅) ( – – ∙ (𝑋̅ 𝑋̅ 𝜇 𝜇) – 𝜇)2 2 ) T o t a l Σ P ( 𝑋̅ ) = Σ P(𝑋̅) ∙ (𝑋̅ – 𝜇)2 = What is now the mean and the variance of the given sampling distribution? 𝑋̅ 1. 5 0 2. 0 0 2. 5 0 3. 0 0 3. 5 0 4. 0 0 4. 5 0 T ot al 𝑋̅ – 𝜇 (𝑋̅ – 𝜇)2 P(𝑋̅) ∙ (𝑋̅ – 𝜇)2 2.2 5 0.225 1.0 0 0.100 0.2 5 0.050 1/ 5 1. 50 1. 00 0. 50 0. 00 0.0 0 0.000 1/ 5 0. 50 0.2 5 0.050 1/ 1 0 1/ 1 0 1. 0 0 1. 00 1.0 0 0.100 1. 50 2.2 5 0.225 P ( 𝑋̅ ) 1/ 1 0 1/ 1 0 1/ 5 ΣP(𝑋̅)∙(𝑋̅– 𝜇)2 =0.750 𝜎 2 𝑥̅ = Σ P(𝑋̅ ) ∙ (𝑋̅ – 𝜇)2 𝜎 2 𝑥̅ = 0.750 Variance of the sampling distribution of the sample mean 64 E. Discussing new concepts and practicing new skill #2 From the activity ask the students to compute the standard deviation by finding the square root of the variance. F. Developing mastery leads to Formative Assessment After the discussion, divide the class into 4 groups and distribute worksheets and materials. Group 1. Construct Me Group 2- Meant to be Group 3.Difference and its Square Group 4:Your Square Root, My Standard G. Making generalization and abstraction about the lesson Give the summary through question and answer. 1. What are the steps in computing the mean, variance and standard Deviation of the sampling distribution of the sample mean? 2. How do you compare mean of the sample means and the mean of population? H. Evaluating Learning J. Additional activities for application or remediation Evaluate the students base on the results of their output. 𝜎𝑥̅ = √Σ P(𝑋̅) ∙ (𝑋̅ – 𝜇)2 = √0.750 𝜎𝑥̅ = 0.87 So, the standard deviation of the sampling distribution of the sample mean is.87 From a group of eight students in your class. Determine the general weighted average of the members of the group and list all possible samples of size 2 and their corresponding mean. Construct the sampling distribution and solve the mean , variance and standard deviation of the sampling distribution of the sample mean. V. REMARKS VI. REFLECTION A. No of learners who earned 80% in the evaluation B. No of learners who require additional activities for remediation who scored below 80% C. Did the remedial lessons work? No. of learners who have caught up with the lesson D. No of learners who continue to require remediation 65 E. Which of my teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/discover which I wish to share with other teachers? 66 Worksheets Group1. Construct Me Given the population 1,3,4,6 and 8. Suppose the sample size of 3 are drawn from this population. Construct the sampling distribution of the Sample Mean Step1. List all possible samples of size 3 and their corresponding mean Sample Mean 2.67 3.33 3.67 4.00 4.33 5.00 5.67 6.00 Step 2 Construct the sampling distribution of the sample means Sample Mean 𝑥̅ Frequency Probability P(𝑥̅ ) Total 67 Sample 1,3,4 1,3,6 1,3,8 1,4,6 1,4,8 1,6,8 3,4,6 3,4,8 3,6,8 4,6,8 Mean 2.67 3.33 4.00 3.67 4.33 5.00 4.33 5.00 5.67 6.00 Sample Mean 𝑥̅ 2.67 3.33 Frequency Probability P(𝑥̅ ) 1 1 1/10 1/10 3.67 1 1/10 4.00 1 1/10 4.33 5.00 2 2 2/10 or 1/5 2/10 or 1/5 5.67 1 1/10 6.00 Total 1 10 1/10 1.00 Group 2: Meant to Be. Solve the mean of the sampling distribution of the mean. Sample Mean 𝑥̅ 2.67 Probability P(𝑥̅ ) 3.67 1/10 4.00 1/10 4.33 2/10 or 1/5 5.00 2/10 or 1/5 5.67 1/10 6.00 1/10 Total 1.00 𝑥̅ ∙ P(𝑥̅ ) 1/10 What is now the mean of the sampling 3.33 of the sample 1/10 distribution mean? Sample Probability Mean P(𝑥̅ ) 𝑥̅ ∙ P(𝑥̅ ) 𝑥̅ ̅) ̅ ∙ P(𝑿 𝜇𝑥̅ 2.67 = 𝚺𝑿 1/10 0.267 𝜇𝑥̅ 3.33 = 4.40 mean1/10 of the sampling 0.333 distribution of the means 3.67 1/10 0.367 4.00 1/10 0.400 4.33 2/10 or 1/5 0.866 5.00 2/10 or 1/5 1.00 5.67 1/10 0.567 6.00 1/10 0.600 total 1.00 Σ𝑥̅ ∙ P(𝑥̅ ) =4.40 Group 3: Difference and its square If the mean 𝜇 of the population is 5. Step 1. Subtract the population mean (𝜇) from each sample (𝑥̅ ). Sampl Probabilit 𝑥̅ - 𝜇 e y Mean P(𝑥̅ ) 𝑥̅ 2.67 1/10 3.33 1/10 3.67 1/10 4.00 1/10 4.33 2/10 or 1/5 5.00 2/10 or 1/5 5.67 1/10 6.00 1/10 2.67 1/10 total 1.00 68 Sampl e Mean 𝑥̅ 2.67 3.33 3.67 4.00 4.33 5.00 5.67 6.00 total Probability P(𝑥̅ ) 𝑥̅ - 𝜇 1/10 1/10 1/10 1/10 2/10 or 1/5 2/10 or 1/5 1/10 1/10 1.00 -1.73 -1.07 -0.73 -0.40 -0.07 0.60 1.27 1.60 Step 2:Square the difference 𝑥̅ - 𝜇 Sampl Probabilit y e 𝑥̅ - 𝜇 (𝑥̅ − 𝜇 )2 P(𝑥̅ ) Mean 𝑥̅ 2.67 3.33 3.67 4.00 4.33 1/10 1/10 1/10 1/10 2/10 or 1/5 2/10 or 1/5 1/10 1/10 1.00 5.00 5.67 6.00 total Sample Mean 𝑥̅ Probability P(𝑥̅ ) 𝑥̅ - 𝜇 (𝑥̅ − 𝜇 )2 2.67 3.33 1/10 1/10 -1.73 -1.07 3.67 4.00 4.33 1/10 1/10 2/10 or 1/5 2/10 or 1/5 1/10 1/10 1.00 -0.73 -0.40 -0.07 2.993 1.145 0.533 0.160 0.005 0.60 0.360 1.27 1.60 1.613 2.560 -1.73 -1.07 -0.73 -0.40 -0.07 5.00 0.60 5.67 6.00 total 1.27 1.60 Group 4: Your Square Root, My Standard Compute the Variance and Standard Deviation of the sampling distribution of the Means if the mean 𝜇 of the population is 5. Step 1: Multiply (𝑥̅ − 𝜇)2 by its corresponding Probability P(𝑥̅ ) and add the results Sample Mean 𝑥̅ 2.67 3.33 3.67 4.00 4.33 5.00 5.67 6.00 total Probabili ty P(𝑥̅ ) 1/10 1/10 1/10 1/10 2/10 or 1/5 2/10 or 1/5 1/10 1/10 1.00 𝑥̅ - 𝜇 P(𝑥̅ )∙ (𝑥̅ − 𝜇)2 Samp le Mean 𝑥̅ Probab ility 2.67 3.33 3.67 4.00 4.33 1/10 1/10 1/10 1/10 2/10 or 1/5 2/10 or 1/5 1/10 1/10 1.00 -1.73 -1.07 -0.73 -0.40 -0.07 (𝑥̅ − 𝜇)2 2.993 1.145 0.533 0.160 0.005 0.60 0.360 5.00 1.27 1.60 1.613 2.560 5.67 6.00 total P(𝑥̅ ) 𝑥̅ - 𝜇 (𝑥̅ − 𝜇)2 -1.73 -1.07 -0.73 -0.40 -0.07 2.993 1.145 0.533 0.160 0.005 0.300 0.115 0.053 0.016 0.001 0.60 0.360 0.072 1.27 1.60 1.613 2.560 0.161 0.256 P(𝑥̅ )∙ (𝑥̅ − 𝜇)2 Σ P(𝑥̅ )∙ (𝑥̅ − 𝜇)2 =0.974 What is now the variance of the sampling distribution of the sample mean? 𝜎 2 𝑥̅ = Σ P(𝑋̅ ) ∙ (𝑋̅ – 𝜇)2 𝜎 2 𝑥̅ = 0.974 Variance of the sampling distribution of the sample mean ̅ ) ∙ (𝑋 ̅ – 𝜇)2 𝜎𝑥̅ = √Σ P(𝑋 = √0.974 𝜎𝑥̅ = 0.990 standard deviation of the sampling distribution of the sample mean 69 Daily Lesson Plan in Statistics and Probability Grade 11/12 Quarter 3 Week 5 I. OBJECTIVES A. Content Standard B. Performance Standard C. Learning Competency/Obj ectives The learner demonstrates understanding of key concepts of sampling ad sampling distributions of the sample mean. The learner is able to apply suitable sampling and sampling distributions of the sample mean to solve real-life problems in different disciplines. M11/12SP-III-e-2. The learner illustrates the Central Limit Theorem. II. CONTENT Central Limit Theorem III. LEARNING RESOURCE References 1. Commission on Higher Education & Philippine Normal University (2016). Teaching Guide for Senior High School: Statistics and Probability. pp.242-261 2. Woodward, E. (2019). Ed's Intro to Prob and Stats. Retrieved from https://legacy.cnx.org/content/col12133/1.1/ pp. 364. 3. Holmes, A., Illowsky, B., & Dean, S. (2019). Retrieved from https://opentxtbc.ca/introbusinessstatopenstax/chapter /usng-the-central-limit-theorem. Other Learning Resource 1. Calculator, manila paper, permanent markers, ruler/meter stick, Diagram of the different shapes of distributions retrieved from http://mathcenter.oxford.emory.edu/site/math117/shap eCenterAndSpread/ IV. PROCEDURES A. Reviewing previous 1. Describe the shape of the following distribution. lessons or presenting the new lesson Image downloaded from http://mathcenter.oxford.emory.edu/site/math117/shapeCenterAndSpread/ 70 Options A. Symmetric, unimodal, bell-shaped B. Uniform C. Skewed right D. Skewed left E. Symmetric, bimodal F. Non-symmetric, bimodal B. Establishing a purpose for the lesson What will be the effect of increasing the sample size on the shape of the sampling distribution of the sample mean given that the samples are selected at random? C. Presenting Examples/Instan ces of the Lesson The learners will be asked to write their hypothesis on their notebook. The teacher will inform the learners that in order to test their hypotheses, they will be asked to perform an activity. At this point, the learners will be divided into six groups. Each group will be given a copy of the worksheet to be used and other materials needed to accomplish the task. The class will be divided into 4 groups. Provide each group with the materials needed in accomplishing their tasks such as dice, Hand-outs, permanent markers, calculator, manila paper and coloring materials. (See attached Hand-outs.) Tasks: Group 1: Construct a probability distribution of the random variable X defined by the outcomes of rolling a die. Draw its corresponding histogram. What is the shape of the distribution? Group 2. Ask one member of the group to roll 2 dice. Consider this as trial 1. Compute the sample mean of the faces showing. For example, 1 and 2, thus the mean is 1+2 = 1.50. Record the outcomes and the mean of the 2 samples on the hand-out provided to your group (Hand-out 1.A) The same person will continue rolling the dice until 20 trials. After completing all the required trials, construct a probability distribution of the sample means and construct its corresponding histogram. Describe the shape of the distribution. Group 3. Ask one member of the group to roll 5 dice. Consider this as trial 1. Compute the sample mean of the faces showing. For example, 1, 3,4,5 and 2, thus the mean 1+3+4+5+2 is = 3.00. Record the outcomes and the mean of 5 the samples on the hand-out provided to your group (Handout 1.B) The same person will continue rolling the dice until 20 trials. After completing all the required trials, construct a probability distribution of the sample means and construct its corresponding histogram. Describe the shape of the distribution. 71 Group 4. Ask one member of the group to roll 10 dice. Consider this as trial 1. Compute the sample mean of the faces showing. For example, 1,1,1,4,4,5,6,2,3 and 2, thus 1+1+1+4+4+5+6+2+3+2 the mean is = 2.90. Record the 10 outcomes and the mean of the samples on the hand-out provided to your group (Hand-out 1.C) The same person will continue rolling the dice until 20 trials. After completing all the required trials, construct a probability distribution of the sample means and construct its corresponding histogram. Describe the shape of the distribution. D. Discussing New concepts and Practicing New Skills # 1 The learners will be given at most 2 minutes to present their group outputs. The teacher then checks the histogram constructed by each group. Once all of the groups’ outputs are checked, ask the learners to compare the histograms of the sampling distributions of the sample mean when n=2, n=5 and n=10 and compare this to the original population distribution constructed by Group 1. What happens to the shape of the sampling of the sample means when the sample size increases? E. Developing Mastery Show the following sets of diagrams to the learners. Let them answer the guide questions afterwards. (A) (B) (C) Images retrieved from https://opentxtbc.ca/introbusinessstatopenstax/chapter/usng-thecentral-limit-theorem Guide Questions 1. What is the shape of the population distribution in Set A? in Set B? in Set C? 72 2. What happens to the shape of the sampling of the sample means when the sample size increases? 3. Complete the statement below about central limit theorem. The central limit theorem for sample means says that as the sample size_________, the sampling distribution of the sample mean grows closer to a ________, regardless of the shape of the original population distribution. (increases, normal distribution) F. Making generalization and abstraction about the lesson G. Evaluating Learning The central limit theorem for sample means says that as the sample size increases, the sampling distribution of the sample mean grows closer to a normal distribution, regardless of the shape of the original population distribution. When the variable has a distribution that is not a Normal distribution, the sample means are not normally distributed unless the sample size is large enough. (Generally, a good rule of thumb is to use a sample size of at least 30, to ensure a sampling distribution that will be approximately normal. Unless of course the original population is known to be normal, in which case the sampling distribution of the sample mean will be guaranteed to normal.) Choose only 1 of the suggested tasks. (See attached worksheets 1-A to 1-D) 73 WORKSHEET 1-A I. Write O if the statement is TRUE and X if otherwise. 1. The Central Limit Theorem tells us that as sample sizes get larger, the sampling distribution of the sample means will become normally distributed, even if the data within each sample are not normally distributed. (TRUE) 2. The shape of the sampling distribution of the means becomes left skewed if random samples of size n becomes larger. (FALSE) 3. The central limit theorem states that as the sample size increases, the shape of the distribution of the sample values look more and more normal. (FALSE) II. Read and analyze the situations below. Write a short explanation for your answer. 4. A certain study involving senior high school students’ number of hours spent in social media in a day shows a strongly skewed distribution with a mean of 5.2 hours and a standard deviation of 2.4 hours. What is the shape of the sampling distribution of the sample means of 55 randomly selected senior high school students if 55 is considered to be a large sample? Justify your answer. 74 WORKSHEET 1-B. What’s Your Muddiest Point? I’m most confused about _____________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ _________________________________________________________________ 75 WORKSHEET 1-C. 3-2-1 Accomplish the table below by writing 3 things that you have learners today, 2 things that you found interesting and 1 question that you still have in mind. Things I learned today 3 Things I found interesting 2 Questions I still have 1 76 WORKSHEET 1-D. T-L-R Accomplish the table below by writing your initial hypothesis in the first column. In the second column, write all the things that you have learned throughout the session and in the third column, write a short reflection about your learnings. Is your hypothesis correct? Can you cite real life situations or phenomena wherein the concept of central limit theorem can be applied? What I think What I learned? Reflection (Write your initial (Write the things that hypothesis before the you learned today.) conduct of the activity) 77 HAND-OUT 1.A SAMPLING DISTRIBUTION OF SAMPLE MEANS (n=2) Name: _______________________ _______________________ _______________________ _______________________ _______________________ _______________________ _______________________ _______________________ Tabulation of Results. Trials Samples (X) Example 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 1,2 Sample Means (round off to the nearest hundredths) ̅) (𝑿 1.50 Complete the probability distribution of the sample means below. You may add columns if needed. ̅) (𝑿 ̅) P (𝑿 Draw the histogram of the sampling distribution of the sample means (n=2). Describe the shape of the distribution. 78 HAND-OUT 1.B SAMPLING DISTRIBUTION OF SAMPLE MEANS (n=5) Name: _______________________ _______________________ _______________________ _______________________ _______________________ _______________________ _______________________ _______________________ Tabulation of Results. Trials Samples (X) Example 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 1, 3,4,5,2 Sample Means (round off to the nearest hundredths) ̅) (𝑿 3.00 Complete the probability distribution of the sample means below. You may add columns if needed. ̅) (𝑿 ̅) P (𝑿 Draw the histogram of the sampling distribution of the sample means (n=2). Describe the shape of the distribution. 79 HAND-OUT 1.C SAMPLING DISTRIBUTION OF SAMPLE MEANS (n=10) Name: _______________________ _______________________ _______________________ _______________________ _______________________ _______________________ _______________________ _______________________ Tabulation of Results. Trials Samples (X) Example 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 1,1,1,4,4,5,6,2,3,2, Sample Means (round off to the nearest hundredths) ̅) (𝑿 2.90 Complete the probability distribution of the sample means below. You may add columns if needed. ̅) (𝑿 ̅) P (𝑿 Draw the histogram of the sampling distribution of the sample means (n=2). Describe the shape of the distribution. 80 Daily Lesson Plan in Statistics and Probability Grade 11/12 Quarter 3 Week 5 I. OBJECTIVES A. Content Standard The learner demonstrates understanding of key concepts of sampling ad sampling distributions of the sample mean. B. Performance Standard The learner is able to apply suitable sampling and sampling distributions of the sample mean to solve reallife problems in different disciplines. C. Learning Competency/Objec tives M11/12SP-III-e-3. The learner defines sampling distribution involving sampling distribution of the sample mean using the Central Limit Theorem. II. CONTENT Sampling distribution involving sampling distribution of the sample mean using the Central Limit Theorem III. LEARNING RESOURCE References 6. Commission on Higher Education & Philippine Normal University (2016). Teaching Guide for Senior High School: Statistics and Probability. pp.242-261 7. Woodward, E. (2019). Ed's Intro to Prob and Stats. Retrieved from https://legacy.cnx.org/content/col12133/1.1/ pp. 364. 8. Holmes, A., Illowsky, B., & Dean, S. (2019). Retrieved from https://opentxtbc.ca/introbusinessstatopenstax/chap ter/usng-the-central-limit-theorem. Other Learning Resource IV. PROCEDURES A. Reviewing previous lessons or presenting the new lesson B. Establishing a purpose for the lesson Calculator, manila ruler/meter stick paper, permanent markers, 2. Recall of the essential formulas for calculating the mean and variance of the sampling distribution of the sample means. Mean of the sampling distribution µ𝑥̅ = 𝑋̅ • 𝑃(𝑋̅) Variance of the sampling distribution 𝜎 2 𝑥̅ = ∑ 𝑃(𝑋̅) − (𝑋̅ − µ)2 What will be the effect of increasing the sample size on the (a) mean and (b) spread of the sampling distribution of the sample mean given that the samples are selected at random? 81 The learners will be asked to write their hypothesis on their notebook. The teacher will inform the learners that in order to test their hypotheses, they will be asked to perform an activity. At this point, the learners will be divided into six groups. Each group will be given a copy of the worksheet to be used and other materials needed to accomplish the task. C. Presenting Examples/Instance s of the Lesson Utilizing the same groupings and accomplished handouts in the previous lesson, the learners will be asked to compute the mean and the standard deviation of the population distribution and of the sampling distribution of the sample means. Group 1. Compute the mean and standard deviation of the probability distribution of the random variable X defined by the outcomes of rolling a die. Group 2. Compute the mean and the standard deviation of the sampling distribution of the sample means (n=2). Group 3. Compute the mean and the standard deviation of the sampling distribution of the sample means (n=5). Group 4. Compute the mean and the standard deviation of the sampling distribution of the sample means (n=10). D. Discussing New concepts and Practicing New Skills # 1 Sampling Distribution of the Sample Means n=2 n=5 Population n= 10 N= 6 Mean Standard Deviation Guide Questions: 1. What happens to the mean/Expected value (EV) of the sampling distribution of the sample means when the sample size increases? 2. What happens to the standard deviation/ standard error (SE) of the sampling distribution of the sample means when the sample size increases? E. Developing Mastery F. Making generalization and abstraction about the lesson The mean of the sampling distribution of the sample mean will always be the same as the mean of the original population regardless of the sample size. 𝝁𝑿̅ = μx ̅ , 𝝈𝑿̅ = 𝝈 , is the The standard deviation of 𝑿 √𝒏 standard error of the mean (SEM) for samples with replacement. 82 If X is a random variable with mean μx and standard deviation σx and either X is normally ̅ ∼ N(μx, 𝛔𝑿 ) distributed or n ≥ 30, then 𝑿 √𝒏 G. Evaluating Learning Choose only one activity from the following activities: Activity 1 (Individual Task) Determine the mean 𝜇𝑋̅ , variance 𝜎𝑋2̅ and standard deviation 𝜎𝑋̅ for each item. 1. A random sample of size 49 is taken with replacement from a population with µ = 82.4 and σ = 60. 2. A random sample of size 36 is taken with replacement from a population with µ = 48 and σ = 6.5. 3. A random sample of size 49 is taken with replacement from a population with µ = 28.6 and σ = 12 4. A random sample of size 36 is taken with replacement from a population with µ = 120 and σ = 20. 5. A random sample of size 100 is taken with replacement from a population with µ = 28.6 and σ = 25. Activity 2. TIC-TAC-TOE (Pair Activity) (see attached guide) Activity 3. What’s Your Muddiest Point? I’m most confused about ____________________________________________ ____________________________________________ ____________________________________________ Activity 4. 3-2-1 Accomplish the table below by writing 3 things that you have learners today, 2 things that you found interesting and 1 question that you still have in mind. Things I learned today 3 2 Things I found interesting Questions I still have 1 83 Activity 2. TIC-TAC-TOE (Pair Activity) This activity will be accomplished by pair. Player 1 will use X mark while Player 2 will use O as his mark. To place a mark, the player must correctly solve the given problem. Players takes turn. The player who succeeds in placing three of their marks in a horizontal, vertical or diagonal row wins the game . A random sample of size 49 is taken with replacement from a population with µ = 82.4 and σ = 60. Find 𝜇𝑋̅ . A random sample of size 36 is taken with replacement from a population with µ = 48 and σ = 6.5. Find 𝜎𝑋̅ . A random sample of size 49 is taken with replacement from a population with µ = 28.6 and σ = 12. Find 𝜎𝑋2̅ . A random sample of size 36 is taken with replacement from a population with µ = 120 and σ = 20. Find 𝜎𝑋2̅ . A random sample of size 100 is taken with replacement from a population with µ = 28.6 and σ = 25. Find 𝜇𝑋̅ . A random sample of size 100 is taken with replacement from a population with µ = 28.6 and σ = 25. Find 𝜎𝑋̅ . A random sample of size 100 is taken with replacement from a population with µ = 28.6 and σ = 25. Find 𝜎𝑋̅ . A random sample of size 100 is taken with replacement from a population with µ = 28.6 and σ = 25. Find 𝜎𝑋2̅ . A random sample of size 100 is taken with replacement from a population with µ = 28.6 and σ = 25. Find 𝜇𝑋̅ . 84 Daily Lesson Plan in Statistics and Probability Grade 11/12 Quarter 3 Week 5-6 I. OBJECTIVES A. Content Standard The learner demonstrates understanding of key concepts of sampling ad sampling distributions of the sample mean. B. Performance Standard The learner is able to apply suitable sampling and sampling distributions of the sample mean to solve reallife problems in different disciplines. C. Learning Competency/Obje ctives M11/12SP-III-e-f-1. The learner solves problems involving sampling distributions of the sample mean. II. CONTENT Solving Word Problems on Sampling Distribution of Sample Mean III. LEARNING RESOURCE Teacher’s Guide pp. 261-264, pp. 191-192 Other Learning Cumulative Distribution Function (CDF) of the Standard Resource Normal Curve TG pp. 191-192 Central Limit Theorem –Worksheet (Mean) Retrieved from https://lhsblogs.typepad.com/files/central-limit-theoremworksheet-mean.pdf IV. PROCEDURES A. Reviewing 1. Find the area under the normal curve given the previous lessons following conditions. or presenting the a. To the left of z = 1 Answer: 0.8849 new lesson b. To the right of z = 1.75 Answer: 0.0401 a. Between z = 0.5 and z = 2.5 Answer: 0.3023 85 b. Between z = -2.5 and z = -1.2 Answer: 0.1089 2. Find the z values for each of the following: a. µ = 50, σ = 4 and X = 45 Answer: z = -1.25 b. µ = 30, σ = 10 and X = 20 Answer: z = 1.00 c. µ = 50, σ = 25 and 𝑋̅ = 45, n = 100. Answer: z = -2.00 d. µ = 30, σ = 10 and 𝑋̅ = 25, n = 25. Answer: z = -2.50 3. Establishing a purpose for the lesson Inform the learners that the aim of the lesson is to solve word problems on sampling distribution of the sample mean. How do we solve word problems on sampling distribution of the sample mean? 4. Presenting Examples/Instanc es of the Lesson Present the following problems to the learners. Fresh Cola uses a filling machine to fill plastic bottles with soda. The contents of every bottle vary according to a normal distribution with µ = 253 ml and σ= 3 ml. (a) What is the probability that an individual bottle contains less than 250 ml? (b) If 10 bottles are randomly selected, what is the probability that the mean of the samples will be less than 250 mL? 5. Discussing New concepts and Practicing New Skills # 1 Guide the students in solving the word problem above. Below are the solutions to the problem. Problem: Fresh Cola uses a filling machine to fill plastic bottles with soda. The contents of every bottle vary 86 according to a normal distribution with µ = 253 ml and σ= 3 ml. a. What is the probability that an individual bottle contains less than 250 ml? Steps Solution 1. Identify the µ = 253 ml given/fact σ= 3 ml s in the X = 250 problem. 2. Identify what is P (X < 250) asked for. 3. Identify the formula to be used? The problem deals with an individual data obtained from the population, so we will use the formula Z= 𝜎 to standardize 250. Z= Z= 𝑋−µ 𝜎 250−253 −3 4. Solve the problem. 𝑋−µ 3 Z= 3 Z = -1 We shall find P (X < 250) by getting the area under the normal curve. P(X < 250) = P (z < -1) = 0.5000 – 0.3413 = 0.1587 5. State the final answer. So, the probability that a randomly selected bottle will contain less than 250 ml is 0.1587 or 15.87%. 87 b. If 10 bottles are randomly selected, what is the probability that the mean of the samples will be less than 250 mL? Steps 1. Identify the given/f acts in the proble m. 2. Identify what is asked for. 3. Identify the formula to be used? Solution µ = 253 ml σ= 3 ml 𝑋̅ = 250 n= 10 P (X < 250) Here, we are dealing with data about the sample means. So, we will use the formula Z= 𝑋̅ −µ 𝜎 √𝑛 to standardize 250. Z= Z= 𝑋̅−µ 𝜎 √𝑛 250−253 3 √10 Z= -3.16 ̅ < -3.16) by getting the We shall find P (𝑋 area under the normal curve. 4. Solve the proble m. ̅ < -3.16) = P (z < -3.16) P (𝑋 = 1.0000– 0.9992 = 0.0008 5. State the final answer . So, the probability that 10 randomly selected bottles will have a mean less than 250 ml is 0.0008 or 0.08%. 88 6. Developing Mastery For Slow learners, use Worksheet 1-A and 1-B. For Average and Advanced learners, use Worksheet 1-C and 1-D. 7. Making generalization and abstraction about the lesson Z= 𝜎 ( used to gain information about an individual data value when the variable is normally distributed.) Z= 8. Evaluating Learning 𝑋−µ 𝑋̅−µ 𝜎 √𝑛 ( used to gain information when applying the central limit theorem about a sample mean when the variable is normally distributed or when the sample size is 30 or more.) For Slow Learners, distribute Worksheet 2-A or 2-B to the learners together with a z-table. For Average and Advanced Learners, distribute both Worksheet 2-A and 2-B to the learners together with the z-Table. 89 WORKSHEET 1- A Duck Eggs Problem: The weights of the eggs produced by a certain breed of ducks are normally distributed with mean 70 grams and standard deviation of 10 grams. What is the probability that one duck egg selected at random weigh more than 75 grams? Steps 1. Identify the given/facts in the problem. 2. Identify what is asked for. 3. Identify the formula to be used? Solution µ= σ= X= P (X > 75) The problem deals with an individual data obtained from the population, so we will use the formula Z= 𝑋−µ 𝜎 to standardize 75. 4. Solve the problem. Z= 𝑋−µ 𝜎 Substitute the values of X, µ and σ. Z= Z= Z= We shall find P (X > 75) by getting the area under the normal curve. P(X > 75) = P (z > ____ ) = ________ 5. State the final answer. So, the probability that a randomly selected duck egg will weigh greater than 75 grams is _______. 90 WORKSHEET 1- B Duck Eggs Problem: The weights of the eggs produced by a certain breed of ducks are normally distributed with mean 70 grams and standard deviation of 10 grams. What is the probability that the average weight of the 12 duck eggs selected at random will be more than 75 grams? Steps 1. Identify the given/facts in the problem. 2. Identify what is asked for. Solution µ= σ= 10 𝑋̅ = n= 12 P (X < 250) 3. Identify the formula to be used? Here, we are dealing with data about the sample means. So, we will use the formula Z= 𝑋̅ −µ 𝜎 √𝑛 to standardize 75. 4. Solve the problem. Z= Z= 𝑋̅−µ 𝜎 √𝑛 10 √12 Substitute the values of 𝑋̅and µ. Z= ̅ > 75) by getting the area We shall find P (𝑋 under the normal curve. ̅ > 75) = P (z > _______ ) P (𝑋 = _____________ 5. State the final answer. So, the probability that 12 randomly selected duck eggs will have a mean greater than 75 grams is ___________. 91 WORKSHEET 1- C Duck Eggs Problem: The weights of the eggs produced by a certain breed of ducks are normally distributed with mean 70 grams and standard deviation of 10 grams. What is the probability that one duck egg selected at random weigh more than 75 grams? Steps 1. Identify the problem. Solution given/facts in the 2. Identify what is asked for. 3. Identify the formula to be used? 4. Solve the problem. 5. State the final answer. 92 WORKSHEET 1- D Duck Eggs Problem: The weights of the eggs produced by a certain breed of ducks are normally distributed with mean 70 grams and standard deviation of 10 grams. What is the probability that the average weight of the 12 duck eggs selected at random will be more than 75 grams? Steps 1. Identify the problem. Solution given/facts in the 2. Identify what is asked for. 3. Identify the formula to be used? 4. Solve the problem. 5. State the final answer. 93 Worksheet 2-A Pregnancy The length of human pregnancies from conception to birth varies according to a distribution that is approximately normal with mean 264 days and standard deviation 16 days. Consider 15 pregnant women from a rural area. Assume they are equivalent to a random sample from all women. (a) What's the probability that a single pregnant woman is pregnant for less than 250 days? Steps Solution 1. Identify the given/facts in the problem. 2. Identify what is asked for. 3. Identify the formula to be used? 4. Solve the problem. 5. State the final answer. (b) What is the probability that the sample mean length of pregnancy lasts for less than 250 days? 94 Steps 1. Identify the problem. Solution given/facts in the 2. Identify what is asked for. 3. Identify the formula to be used? 4. Solve the problem. 5. State the final answer. 95 Worksheet 2-B. Life Expectancy A certain study on the life expectancy of people in a Country A revealed that the mean age at death was 80 years and the standard deviation was 10 years. (a) What is the probability that an individual selected at random will be less than 50 years old? Steps Solution 1. Identify the given/facts in the problem. 2. Identify what is asked for. 3. Identify the formula to be used? 4. Solve the problem. 5. State the final answer. 96 (b) If a sample of 100 people from this country is selected, find the probability that the mean life expectancy will be less than 50 years. Steps Solution 1. Identify the given/facts in the problem. 2. Identify what is asked for. 3. Identify the formula to be used? 4. Solve the problem. 5. State the final answer. 97 Daily Lesson Plan in Statistics and Probability Grade 11/12 Quarter 3 Week 6 I. OBJECTIVES A. Content Standard The learner demonstrates understanding of key concepts of estimation of population mean an population proportion. B. Performance Standard The learner is able to estimate the population mean and population proportion to make sound inferences in real-life problems in different disciplines. C. Learning Competency/Obj ectives M11/12SP-III-f-2. The learner illustrates point and interval estimations. M11/12SP-III-f-3. The learner distinguishes between point and interval estimations. II. CONTENT Point and Interval Estimations III. LEARNING RESOURCE Teacher’s Guide pp. 316-319 Other Learning Resource IV. PROCEDURES A. Reviewing previous lessons or presenting the new lesson B. Establishing a purpose for the lesson Meta-cards of different colors, permanent marker, masking tape Frayer Model diagram School Division, S. (2018, October 29). Frayer Model. OER Commons. Retrieved July 24, 2019, from https://resourcebank.ca/authoring/1499-frayer-model. A quick review of the concept of parameter and statistic will be made before discussing the concept of Point and Interval estimate. Task 1. Parameter & Statistic Below are measures that describe some characteristics of a given sample or population. Raise your right hand if the identified measure is a statistic. If the given measure is a parameter, raise your left hand. 1. Sample mean (𝑥̅ ) 2. Population mean (µ) 3. Sample variance (𝑠2 ) 4. Population variance (σ2 ) 5. Sample standard deviation (s) 6. Population standard deviation (σ) 7. Sample proportion (𝑝̂ ) 8. Population proportion (p) At this point, reiterate to the learners that in reality, we do not have the whole population to work on. Hence, a representative obtained through random sampling is important in making inference about the population and or 98 its parameters. In making inferences about the population, learners can either provide a value or values for the parameter or evaluates a statement about a parameter. Inform the learners that the focus of the lesson is on the two ways of estimation (point and interval estimation) and differentiate one from another. C. Presenting Examples/Instan ces of the Lesson Task 2. Guessing Game (This is a modified activity of the activity found in TG p. 317) Distribute three meta-cards to the learners. The learners will be asked answer the statements/phrases below by writing their responses on specified meta-cards. Red Meta1. His/her “best” guess of your age by card giving a single number Yellow meta- 2. His/her “best guess of the range card wherein your age will likely fall. Green metacard 3. His/her confidence from 0% (not confident) to 100% (very confident) in his/her educated guess of the range of values un number 2. Afterwards, ask the learners to post their responses on the specific posting area for each color of the meta-card. Randomly pick three students to briefly explain his/her basis for his/her written response. Note: Aside from teacher’s age, other variables such as price of rice, daily allowance, etc. can also be used. D. Discussing New concepts and Practicing New Skills # 1 1. Discuss the responses on the activity to the learners, emphasizing the following points: a. There are no right or wrong numerical value for the given answers. However, there might be misconceptions or misunderstanding of the concepts when they provided answers. b. On the red meta-cards, the learners should have written one logical number between 21 and 65 (inclusive). Their guess of your age should be between 21 and 65 for it to be logical since one usually starts working at the age of 21 and retires at the age of 65 (compulsory retirement age). c. On the yellow meta-card, the learners should have written a logical range of values or set of values with upper and lower limits. The lower limit should be at least 21 while the upper limit should be at most 65. d. On the green meta-card, the learners should have written a percentage within 0% to 100%. 99 Inform the learners of your true age. Take note also of how many learners gave the correct point estimate and confidence interval estimate that included your age. 2. Inform the learners that the numbers that they wrote on the red meta-cards can be considered point estimate. The range of values or set of values that they wrote on the yellow meta-cards can be considered as interval estimate. The percentage that they wrote on the green meta-cards can be considered as confidence coefficient. When interval estimate is combined with confidence coefficient, it is now referred to as confidence interval estimate. Task 3. Let’s define the Estimates Note: For Advanced learners, let them accomplish the Frayer model below by groups. For average and slow learners, you may want to present them with an accomplished Frayer model for Point estimate and Interval estimate. For group 1 and 2 Definition A point estimate is a numerical value and it identifies a location or position in the distribution of possible values. Characteristics - Single value as estimate - There are two possibilities (right or wrong) - No confidence coefficient involved Point estimate Examples The mean volume of 11 bottles of cola is 12 oz. On the average, there are 89 customers in the restaurant. 100 Non-Examples The mean volume of 11 bottles of cola ranges from 12-13 oz. On the average, there are 89-100 customers in the restaurant. For group 3 and 4 Definition An interval estimate is a range of values where most likely the true value will fall. Characteristics - More than one possible values as estimates - Involves confidence coefficient Interval estimate Examples Non-Examples The mean volume of 11 bottles of cola ranges from 12-13 oz. On the average, there are 89-100 customers in the restaurant. On the average, there are 89 customers in the restaurant. The mean volume of 11 bottles of cola is 12 oz. Note: The Frayer Model is a graphical organizer used for word analysis and vocabulary building. This four-square model prompts students to think about and describe the meaning of a word or concept by (a) Defining the term, (b) Describing its essential characteristics, (c) Providing examples of the idea, and (d) Offering non-examples of the idea. (Sun West School Division, 2018) E. Discussing New Task 4. Compare and Contrast concepts and Using the Venn Diagram below, compare and contrast Practicing New “Point Estimation” and “Interval Estimation”. Skills # 2 Note: For Advanced learners, let them accomplish the Venn diagram below by group but for average and slow learners, you may want to give them choices. Point Estimation 101 Interval Estimation F. Developing Mastery Task 5. Is it true? Get a piece of paper. Your teacher will a statement for you. If the statement is correct, write TRUE. Otherwise, write FALSE. 1. The sample statistic s (sample standard deviation) is a point estimator. 2. The population mean (µ) is a point estimator. 3. The sample mean (𝑥̅ ) is a point estimate of the population mean (µ) 4. The sample proportion (𝑝̂ ) is an interval estimate of the population proportion p. 5. In the statement, “About 80%-85% of the youths in Sorsogon City voted during the SK election.”, the phrase “about 80%-85% denotes an interval estimate. 6. Point and Interval estimates of a population parameters are from sample statistic. G. Finding Application of Can you cite other real-life phenomenon involves point Concepts in estimate? How about real-life phenomenon involves Daily Living interval estimate? H. Making generalization and abstraction about the lesson I. Evaluating Learning A point estimate is a numerical value and it identifies a location or position in the distribution of possible values. A point estimate of a population parameter is a single value of a sample statistic. An interval estimate is a range of values where most likely the true value will fall. Directions. The statements below contain statistic which can be classified as either point estimate or an interval estimate. Read each item carefully and write PE if the underlined measure is a point estimate and IE if interval estimate. 1. The average weight of 12 Grade 11 students is 50.5 kilograms. 2. The average wait time in Restaurant A is 10 minutes. 3. 49 Grade 11 students were asked about their age and recorded a mean age of 17 years old. 4. The average weight of 100 randomly selected mangoes in the crate ranges from 10 grams to 20 grams. 102 5. The average time spent for social media of 20 randomly selected Grade 11 students is 4 hours in a day. 6. The average weight of newborn babies in Hospital A is around 2.6 kg to 3.6 kg. 7. 10 out of 50 randomly selected professionals are in favor of the implementation of national ID. 8. The mean weight of 40 randomly selected Grade 7 students is around 40 to 45 kilograms. 9. The age of beginning Grade 1 pupil is 6-7 years old. Note: The evaluation can also be implemented through a pair-work in in a form of a game called Tic-Tac-Toe. See attached sample Tic-Tac-Toe Board 103 Tic-Tac-Toe This activity will be accomplished by pair. Player 1 will use X mark while Player 2 will use O as his mark. To place a mark, the player must correctly identify whether the highlighted estimator is a point estimate or an interval estimate. Players takes turn. The player who succeeds in placing three of their marks in a horizontal, vertical or diagonal row wins the game. The average weight of 12 Grade 11 students is 50.5 kilograms. The average weight of 100 randomly selected mangoes in the crate ranges from 10 grams to 20 grams. 10 out of 50 randomly selected professionals are in favor of the implementation of national ID. The average wait time in Restaurant A is 10 minutes. 49 Grade 11 students were asked about their age and recorded a mean age of 17 years old. The average time spent for social media of 20 randomly selected Grade 11 students is 4 hours in a day. The average weight of newborn babies in Hospital A is around 2.6 kg to 3.6 kg. The mean weight of 40 randomly selected Grade 7 students is around 40 to 45 kilograms. 104 The age of beginning Grade 1 pupil is 6-7 years old. Daily Lesson Plan in Statistics and Probability Grade 11 I. OBJECTIVES A. Content Standard B. Performance Standard C. Learning Competency/Objectives Write the LC code for each II. CONTENT III. LEARNING RESOURCES I. Reference Teacher’s Guide pages Learner’s Material pages Textbook pages Additional Materials from Learning Resource(LR) Portal J. Other Learning Resources IV. PROCEDURES A. Reviewing previous lesson or presenting the new lesson The learner demonstrates understanding of key concepts of estimation of population mean and of population proportion. The learner is able to estimate the population mean and population proportion to make sound inferences in real-life problems in different disciplines. The learner identifies point estimator for the population mean M11/12SP-IIIf-4 Estimation of Parameters Statistic and Probability by Belencina, Baccay & Mateo pp.179-183 Senior High Conceptual Math and Beyond Statistics and Probability pp. 146-151 1. 2. 3. 4. 1 fair coins, Manila paper, pentel pen, projector, laptop Preliminary Activity: Word Scramble(Power Point Presentation)) Unscramble the list of letters found at the screen, to spell out words . answer U N Population T Point Estimator T O T O P P I O M I T S A R S Sample Mean N Proportion B. Establishing a purpose for the lesson C. Presenting examples/instances of the new lesson Tell the class about the objectives of the lesson on how proportions about populations are expressed and computed. Present examples to the class( PPT) Great Escape On a typical morning Anthony ask his TV viewers if they believe or do not believe the “great escape” story of a group of soldiers 105 from a perceived adversary. At the end of the show, he reported that 68% of the respondents believe the story. Guided Question: What does the report meant to you? What do you understand by the expression 68%? D. Discussing new concepts and practicing new skills #1 Discuss further the example presented and answer the guided question. 1) 68% is also called proportion 2)Percentages are preferred when reporting frequencies of subsets of population. 3)On computing percentage are first converted to proportions in decimal form. 4) Proportion also represent probabilities. So, the probability that all TV viewers favor the great escape story id 0.68. 5) And that who do not favor is 1 – 0.68 = 0.32 or 32% E. Discussing new concepts and practicing new skill #2 Tell the class that the percentage expression is called proportion. Have them define the proportion. Proportion – is a fraction expression with the number of favorable responses on the numerator and the total number of respondents on the denominator Continue the discussion on how to solve the sample proportion. Use the symbol for the discussion of the probability n = number of observations in simple random sample 𝑝 = population proportion 𝑝̂ = sample proportion (read “p hat”) Where: 𝑝̂ = 𝑥 (𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑑𝑒𝑠𝑖𝑟𝑒𝑑 𝑜𝑢𝑡𝑐𝑜𝑚𝑒𝑠) 𝑛(𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑠𝑎𝑚𝑝𝑙𝑒 𝑒𝑙𝑒𝑚𝑒𝑛𝑡𝑠) F. Developing mastery leads to Formative Assessment Activity 3: Differentiated Activities Divide the class into three groups and distribute the manila paper, pentel pen and worksheet . Remind the students to read carefully the instruction. Ask the group to select their leader and present the output to the class. Group 1: NEW KIND OF SNACKS Group 2: My Head and My Tail Group 3: Job Satisfaction G. Finding practical application of concept and skill in daily living. Ask the students how useful are proportions in the reports of survey results? Possible answer: 1. To determine the easiest and convenient way the population proportion. e. A sort of summarizing H. Making generalization and abstraction about the lesson Give the summary of the lesson through 106 Answers: question and answer 1. What is the mean of the sampling distribution of 𝑝̂ ? 2. What is the point estimator of the population proportion p? 3. What is the formula use to solve the point estimator of p? I. Evaluating Learning 1. p 2. 𝑝̂ where 3. 𝑝̂ = 𝑥 (𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑑𝑒𝑠𝑖𝑟𝑒𝑑 𝑜𝑢𝑡𝑐𝑜𝑚𝑒𝑠) 𝑛(𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑠𝑎𝑚𝑝𝑙𝑒 𝑒𝑙𝑒𝑚𝑒𝑛𝑡𝑠) and 𝑞̂ = 1- 𝑝̂ Evaluate the results by counting the correct answer from the Formative Test J. Additional activities for application or remediation V. REMARKS VI. REFLECTION A. No of learners who earned 80% in the evaluation B. No of learners who require additional activities for remediation who scored below 80% C. Did the remedial lessons work? No. of learners who have caught up with the lesson D. No of learners who continue to require remediation E. Which of my teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/discover which I wish to share with other teachers? 107 Group 1 Worksheet 1 NEW KIND OF SNACKS Activity 1: New kind of snacks A random selection of school children were asked whether they Like (1), Do not Like (0) whether they like or not, a new kind of snacks served by the school cafeteria. 1 0 1 1 1 1 1 0 0 1 0 1 0 0 0 Procedure: 1. Tally the responses on the table Response Tally Like(code 1) Do not Like (code 0) Cannot decide (code 2) 1 1 1 1 1 1 1 1 1 0 1 0 1 1 0 Frequency Total 3. Write the tally marks as whole numbers. 4. Complete the entries in the table 5. Answer the guided questions: a. What is the proportion of respondents who like the new snacks? b. What is the proportion of respondent who do not like the new snack? c. What is the prop Answers: Response Like(code 1) Do not Like (code 0) Tally IIII – IIII- IIII-IIII IIII - IIII Total Frequency 20 10 30 5. Answer the guided questions: a. What is the proportion of respondents who like the new snacks? 𝑝̂ = = 𝑥 𝑛 20 30 𝑝̂ = 0.67 or 67% b. What is the proportion of respondent who do not like the new snack? 𝑞̂ = 1- 𝑝̂ = 1- 0.67 𝑞̂ = 0.33 or 33% 108 Group 2 Worksheet 2 Getting the Head Do the following task 1. Toss a fair of coin 10 times. 2. Record the result in the table. Use 0 for heads and 1 for tails. 1st Trial Head Tails 3. Counts the number of heads occurring and denote this as x 4.Compute 𝑝̂ = 𝑥 𝑛 for the first trial. This is called 𝑝̂1 5. Repeat step 1 to 3 times 2nd Trial Head Tails 3rd Trial Head Tails 6. Compute the mean or average of the 𝑝̂ values 𝑝̂= 𝑝̂1 + 𝑝̂2 + 𝑝̂3 3 What is now, the point estimator of the population proportion p? 7. Compute the proportion of getting Tail using the formula 𝑞̂ = 1- 𝑝̂ Group 3 Worksheets 3 Nora conducted a survey for a fast food restaurant owner who wanted to know the level of acceptability of a new food combo among customer. A tally of the frequencies yielded the following results. Frequency (f) Very Acceptable (VA) 182 Acceptable (A) 74 Guided Question: 1. What is the total number of respondents?(n) 109 2. What percentage of the respondents find the new food combo very acceptable?( 𝑝̂ ) 3. What percentage of the respondents fond the new food combo acceptable?( 𝑞̂ Answers: 1. 256 2. 182 3. 29% 110 School Teacher Grade Level Learning Area Time & Date Quarter I. Objectives A. Content Standard B. Performance Standard C. Learning Competencies/ Objectives II. Topic A. References B. Teacher’s guide pages C. Learner’s material pages D. Textbook pages E. Additional materials from learning resource portal F. Other learning resources III. Procedure 11 Statistics and Probability 3rd The learner demonstrates understanding of key concepts of estimation of population mean and population proportion. The learner is able to estimate the population mean and population proportion to make sound inferences in reallife problems in different disciplines. M11/12SP-IIIF-4 and M11/12SP-IIIF-5 1. Explain the how to determine the point estimate of the population mean. 2. Identify point estimator for the population mean. 3. Compute for the point estimate of the population mean. Point Estimate Mercado, Jesus P., et al., Next Century Mathematics Statistics and Probability, 2016 Belecina, Rene R., et al., Statistics and Probability, 2016 pen, board, calculators, visual aids A. Reviewing Daily routine (opening prayer, checking of attendance) previous lesson What do you mean by parameter? and presenting the In what situation in the field of business, agriculture, new lesson education, technology and health you use or take sample to describe the characteristics of the population? Is it valid or acceptable? Why? Present a picture of group of people or crowd. According to reports, there are 500,000 people who attended the PenafraciaTranslacion. Source: Nino N. Luces/ Manila Bulletin File Photo 111 What you do think is the basis of the said report? Did the reporter count the actual number of participants? B. Establishing the purpose of the lesson C. Presenting a examples/ instances of a new lesson Present the learning objectives. (Write or post the learning objectives on the board) How can you estimate the lifespan or life expectancy of Filipinos? Provide a set of data showing the lifespan of 30 Filipinos: 82 65 72 78 67 78 75 39 82 67 75 78 78 50 78 48 67 58 34 58 78 91 75 40 88 68 70 78 93 66 Divide the class into four(4) groups and let the muse their calculator to determine the average lifespan of: Set A: Any five (5) randomly selected data Set B: First ten(10) data (first row) Set C: First twenty (20) data (first two rows) Set D: All the given (30) data Let each group representative present their answer on the board. Ask the class to compare the different results. Guide questions: What can you say about the computed mean from Set A, B and C? Which of answer is closer to the population mean (Set D)? What if we will take 25 randomly selected sample scores, how would you describe its mean in relation to the entire population mean? Relate students’ answer(s) to Central Limit Theorem. (If random samples of size n are drawn from a population, then as n becomes larger, the sample means approaches the normal distribution, regardless of the shape of the population distribution.) D. Discussing new concepts and practicing new skills #1 Emphasize to the class that the previous activity is a process of point estimation State and discuss the meaning of: - Estimation is the process of finding parameter value. 112 - E. Discussing new concepts and practicing new skills #2 Estimate is a value or range of values that approximate a parameter based on sample statistics computed from sample data. Point Estimate is a specific numerical value of the population parameter. Based from the previous example: a) What population parameter we used to estimate the population? b) Why do we use mean as point estimator instead of median or mode? Emphasize the advantages of using mean and the limitations of median and mode as point estimator. Identify the sample mean, median and mode of the given data and compare it to the population mean. c) What are the other properties of good estimator? Considering the same data above (the life expectancy of 30 Filipino samples), do you think the average or mean of the means from each column of data will be the same as your answer in set D? Why? 82 65 72 78 67 78 75 39 82 67 75 78 78 50 78 48 67 58 34 58 78 91 75 40 88 68 70 78 93 66 Can you consider the mean of the means as the point estimate of the population parameter? Emphasize to the students the difference between the mean of the means of: (a) samples and (b) population. F. Developing Mastery Activity: “Do you know me?” 1. Ask each student to estimate Grade 11 students’ profile by determining the averages of each of the following: number of siblings, weight, height, average daily allowance and sleeping time. Let them write the answers in their notebook. 2. By group, let them gather basic information about their classmates’ profile: a. Number of siblings in the family (Group 1) b. Weight (Group 2) c. Height (Group 3) d. Average daily allowance (Group 4) e. Sleeping time (Group 5) Let each group representative present their findings. Ask: Are the estimated averages/ means the same as the actual class means? What makes your estimate afar or closer to the actual mean? 113 G. Finding Practical Applications of Concepts and skills in daily life H. Making Generalization and abstraction about the lesson Think –Pair - Share What is the importance of point estimate? Think of instances or real life situations where estimation is used in the field of technology, science and economics. By dyad: share your insights or answers to your partner. Ask at least 10 student–representatives to present their answers to the class. I. Evaluating Activities What are the significant learning you gained from our lesson today? What is the point estimator of the population mean? How do you calculate the point estimate of the population mean? Why is it important to determine the point estimate of the population mean? Compute the point estimate of the population mean for the given data. Math Quiz Scores of 30 students randomly selected from Grade 11 and 12 classes 23 33 44 41 34 J. Additional Activities for Application or Remediation V-REMARKS 39 45 38 31 43 48 38 38 44 46 38 41 40 40 26 33 27 42 37 45 46 45 27 28 38 Gather data on the cellular phone load expense of 50 students in our school and find its mean. What are the implications of the data/ information you gathered? VI-REFLECTION A. No. Of learners who earned 80% on the formative assessment B. No.of learners who require additional activites for remediation. C. Did the remedial lesson work? No. of learners who have caught up with the lesson. 114 D. No. of learners who continue to require remediation E. Which of my teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/ discover which I wish to share with other teachers? 115 School Teacher Time and Date Grade Level Learning Area Quarter 11 MATHEMATICS 3rd I. OBJECTIVES A. CONTENT STANDARD B. PERFORMANCE STANDARD C. LEARNING COMPETENCIES / OBJECTIVES (Write the LC Code for each) II. CONTENT III. LEARNING RESOURCES A. References 1. Teacher’s Guide pages 2. Learner’s Material pages 3. Textbook pages 4. Additional Materials from Learning Resource (LR) portal B. Other Learning Resources IV. PROCEDURE A. Presenting the new lesson. B. Establishing a purpose for the lesson. The learner demonstrates understanding of key concepts of estimation of population mean and population proportion. The learner is able to estimate the population mean and population proportion to make sound inferences in real-life problems in different disciplines. Identifies the appropriate form of the confidence interval estimator for the population mean when: (a) the population variance is known, (b) the population variance is unknown, and (c) the Central Limit Theorem is to be used. (M11/12SP-IIIg-1) Interval Estimation for a Mean Statistics and Probability for Senior High School Authors: Christian Paul O. Chan Shio & Maria Angeli T. Reyes Pages 194 - 200 ADVANCED LEARNERS AVERAGE LEARNERS In the previous lesson, you have learned how to construct a point estimator of a population parameter. However, a much better method for estimating a parameter would be to incorporate a “margin of error” to construct an interval that contains the true parameter value. This method is called interval estimation. In interval estimation, two numbers are calculated based on sample data, forming an interval where the parameter’s value is expected to lie. In this case, the formula is called interval estimator, while the range of values obtained is called interval estimate or a confidence interval. The confidence coefficient, denoted by 1 – ά, is the probability that a confidence interval will contain the estimated parameter. 116 Confidence Interval for the Population Mean (large sample or normal population, σ is known) A (1 – ά) 100% confidence interval for μ is given by 𝜎 𝜎 (𝑥̅ − 𝑧ά ∙ , 𝑥̅ + 𝑧ά ∙ ) 2 √𝑛 2 √𝑛 where 𝑥̅ = sample mean; 𝑎 𝑧ά = z-value that leaves an area of to the 2 2 right; 𝜎 = population standard deviation; and 𝑛 = sample size Confidence Interval for the Population Mean (large sample, σ is unknown) A (1 – ά) 100% confidence interval for μ is given by 𝑠 𝑠 (𝑥̅ − 𝑧ά ∙ , 𝑥̅ + 𝑧ά ∙ ) √𝑛 √𝑛 2 2 where 𝑥̅ = sample mean; 𝑎 𝑧ά = z-value that leaves an area of to the 2 2 right; 𝑠 = sample standard deviation; and 𝑛 = sample size C. Presenting examples / instance of the new lesson. Example 1: Find and interpret a 95% confidence interval for the population mean given that 𝑛 = 36, 𝑥̅ = 13.1, 𝑎𝑛𝑑 𝜎 = 3.42. Example 1: Find and interpret a 95% confidence interval for the population mean given that 𝑛 = 64, 𝑥̅ = 15.4, 𝑎𝑛𝑑 𝑠 = 2.27. D. Discussing new concepts and practicing new skills. Solution for example 1: For a 95% confidence interval, 1 – ά = 0.95, so ά = 0.05. Using the z – table, we have 𝑧ά = 𝑧0.05 = 𝑧0.025 = 2 2 1.96. Substituting these values into the formula for the confidence interval for a population mean when σ is known, we have 𝜎 𝜎 (𝑥̅ − 𝑧ά ∙ , 𝑥̅ + 𝑧ά ∙ ) 2 √𝑛 2 √𝑛 3.42 3.42 = (13.1 − 1.96 ∙ , 13.1 + 1.96 ∙ ) √36 √36 = (13.1 − 1.12, 13.1 + 1.12) = (11.98, 14.22) Thus, we can be 95% confident that the interval (11.98, 14.22) contains the true value of the population mean. Solution for example 2: 117 For a 95% confidence interval, 1 – ά = 0.95, so ά = 0.05. Using the z – table, we have 𝑧ά = 𝑧0.05 = 𝑧0.025 = 2 2 1.96. Substituting these values into the formula for the confidence interval for a population mean when σ is unknown, we have 𝑠 𝑠 (𝑥̅ − 𝑧ά ∙ , 𝑥̅ + 𝑧ά ∙ ) 2 √𝑛 2 √𝑛 2.27 2.27 = (15.4 − 1.96 ∙ , 15.4 + 1.96 ∙ ) √64 √64 = (15.4 − 0.56, 15.4 + 0.56) = (14.84, 15.96) Thus, we can be 95% confident that the interval (14.84, 15.96) contains the true value of the population mean. E. Developing Mastery. F. Finding practical applications of concepts and skills in daily living. G. Making generalizations and abstraction about lesson. H. Evaluation Let’s Practice: Find and interpret a (1 – ά) 100% confidence interval for the population mean μ given the following values: a. ά = 0.05, 𝑛 = 64, 𝑥̅ = 14.1, 𝜎 2 = 4.32 b. ά = 0.01, 𝑛 = 36, 𝑥̅ = 7.23, 𝑠2 = 0.3047 c. ά = 0.10, 𝑛 = 98, 𝑥̅ = 66.3, 𝑠2 = 2.48 Calvin owns a water refilling station in his neighbourhood. To assess the efficiency of his company’s operation, he decided to do a study of the water consumption of his costumers. He selected 45 households at random where the number of liters (L) of water consumed by each household during the past six months was recorded. The average consumption was found to be 134.6 L with a standard deviation of 21.1 L. What is a 95% confidence interval for the mean water consumption during the past six months among his company’s customers? How do you compute the confidence interval estimate based on the appropriate form of the estimator for the population mean? How do you solve problems involving confidence interval estimation of the population mean? 1.) Find and interpret a (1 – ά) 100% confidence interval for the population mean μ given the following values: a. ά = 0.01, 𝑛 = 100, 𝑥̅ = 18.5, 𝜎 2 = 9.27 b. ά = 0.10, 𝑛 = 49, 𝑥̅ = 7.23, 𝑠2 = 4.47 c. ά = 0.05, 𝑛 = 81, 𝑥̅ = 66.3, 𝑠2 = 6.23 2.) A random sample of 10 chocolate energy bars of a certain brand has, on the average, 230 calories with known population standard deviation of 15 calories. Construct and interpret a 99% confidence interval for the mean calorie content of this brand of energy bar. Assume that the distribution of calories is approximately normal. 3.) A commonly used IQ test is scaled to have a mean of 100 and a standard deviation of 15. A school 118 counsellor was curious about the average IQ of the students in her school and took a random sample of forty students’ IQ scores. The average of these scores was 107.9. Find a 95% confidence interval for the mean student IQ in the school. V. REMARKS (Indicate special cases including but not limited to continuation of lesson plan to the following day in case of re-teaching or; lack of time, transfer of lesson to the following day, in cases of class suspension, etc.) VI. REFLECTION (Reflect on your teaching and assess yourself as a teacher. Think about your student’s progress. What works? What else needs to be done to help the students learn?) A. No. of learners who earned 80% in the evaluation. B. No. of learners who require additional activities for remediation who scored below 80% C. Did the remedial lessons work? No. of learners who have caught up with the lesson D. No. of learners who continue to require remediation E. Which of my teaching strategies worked? Why did these work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/discover which I wish to share with other teachers? 119 ANSWER KEY: Let’s Practice: a. (13.59, 14.61) We can be 95% confident that the interval (13.59, 14.61) contains the true value of the population mean. b. (6.99, 7.47) We can be 99% confident that the interval (6.99, 7.47) contains the true value of the population mean. c. (66.04, 66.56) We can be 90% confident that the interval (66.04, 66.56) contains the true value of the population mean. Practical Problem: A 95% confidence interval for the mean water consumption is (128.44, 140.76) Evaluation: 1. a. (17.72, 19.28) We can be 99% confident that the interval (17.72, 19.28) contains the true value of the population mean. b. (6.73, 7.73) We can be 90% confident that the interval (6.73, 7.73) contains the true value of the population mean. c. (65.76, 66.84) We can be 95% confident that the interval (65.76, 66.84) contains the true value of the population mean. 2. A 99% confidence interval for the mean calorie content of this energy bar is (217.92, 242.21). We can therefore be 99% confident that the true mean calorie content of this brand of energy bar is between 217.79 and 242.21 calories. 3. A 95% confidence interval for the mean student IQ in the school is (103.25, 112.55) 120 121 School Teacher Time and Date I. Objectives A. Content Standard B. Performance Standard C. Learning Competencies/ Objectives II. Topic A. References B. Teacher’s guide pages C. Learner’s material pages D. Textbook pages E. Additional materials from learning resource portal F. Other learning resources IV. Procedure A. Reviewing previous lesson and presenting the new lesson Grade Level Learning Area Quarter 11 MATHEMATICS 3rd The learner demonstrates understanding of key concepts of estimation of population mean and population proportion. The learner is able to estimate the population mean and population proportion to make sound inferences in reallife problems in different disciplines. 1. Explain the process on how to determine the t– distribution value. 2. Illustrate the t– distribution 3. Construct a t– distribution M11-12SP-IIIg-2 and m11-12sp-IIIg-3 t – Distribution Mercado, Jesus P., et al., Next Century Mathematics Statistics and Probability, 2016 Belecina, Rene R., et al., Statistics and Probability, 2016 pen, board, calculators, visual aids, pentel pen, manila papers Daily routine (opening prayer, checking of attendance) Recall the properties of normal distribution: Ask a student to illustrate the graph of normal distribution. Call other set of students to label the components of the normal curve (line of symmetry, asymptote, location of measures of central tendency and standard deviation) B. Establishing the Emphasize that there are situations that can be treated by normal distribution, t– distribution instead. purpose of the lesson Present the learning objectives. (Write or post the learning objectives on the board) C. Presenting a examples/ instances of a new lesson Given a normal distribution curve, show the t distribution curve. Let the students compare and contrast the two curves. 122 Normal distribution df= 1 df= 3 -6 -4 -2 0 2 4 6 Present and discuss the conditions when to use t– distribution and its formula. t= x - s/ n where: x = sample mean = population mean s = standard deviation of the sample n = sample size Emphasize to the class that the computed t- value needs to be compare to the critical t- tabular value. Guide the students on how to determine the degree of freedom and how to find the critical t value given the sample size (refer to the Table of t critical values). D. Discussing new concepts and practicing new skills #1 Let the students find the critical t- value given the following data: 1) n = 10; confidence level = 95% ; one tail 2) n = 18; confidence level = 99% ; two tails 3) n = 25; confidence level = 90% ; one and two tails Ask at least 4 students to illustrate t -distribution curves of the given data above with its corresponding critical value. Let others students evaluate the answers and illustrations of their classmates. E. Discussing new concepts and practicing new skills #2 Let us try to use t- distribution to solve this problem: A group of Grade 12 Practical Research 2 students, conducted a survey regarding the family profile of SHS students in terms economic status. Based from the data collected, they are suspecting that it is significantly lower than the national record stating that the Filipino families average monthly income is P22,000. Is their suspicion correct? Use 95% confidence level. Below are the monthly income (in thousands) of 16 respondents: 123 Present to the class the steps on how to determine the t-value. Ask the class to perform the following: Step 1: Find the mean and standard deviation. Mean = 21 and Standard deviation = 7.81 Step 2: Find the degree of freedom df = n – 1 = 16 – 1 = 15 Step 3: Find the critical tabular t- value Using the table of critical t- value where = 5% and df= 15. The critical value is 2.131 Step 4: Compute the t- distribution value t= x - s/ n 21- 22 -1 = = = -0. 5122 7.81/ 16 1. 9525 Ask the students to plot the critical and computed tvalues in the curve. -2.131 -0. 5122 F. Developing Mastery -2.131 Lead the class to interpret the result and formulate conclusion. - Is the suspicion of the group of Grade 12 researchers correct? Justify your answer. Group Activity: Divide the class into five groups and let each group perform the given task. In your respective group, calculate and illustrate the value of t- distribution. Formulate appropriate conclusion. 124 Group Group Group Group Group 1 2 3 4 5 Sample mean Population mean Standard deviation Sample size Confidence level ; two- tails 12 21 35. 5 60 120. 5 14 18. 5 40.22 58.1 132.4 3 5 10 6.2 4. 5 25 12 16 20 10 90 % 95% 99% 90 % 95% Gallery Walk: Ask each group to post their solution on the wall/ board. Let other groups evaluate each solution or answer. Note: While other members are roaming around, one member from each group should stay in their post to present the solution and answer possible questions of other groups. G. Finding Practical Applications of Concepts and skills in daily life What is the importance of t- distribution in decision making? Let at least five students cite real- life situations where they can apply the concept of t-distribution. H. Making Generalization and abstraction about the lesson What new insights you gained from our lesson today? What is t distribution? What are the steps in construct t- distribution? I. The mean scores of a random sample of 22 TVL students in General Mathematics test is 43. If the standard deviation of the scores is 6.2 and population mean scores is 40.4, find the t- distribution value and describe the result. Use 90 % confidence level, two-tails. Evaluating Activities J. Additional Activities for Application or Remediation V-REMARKS VI-REFLECTION 125 School Teacher Time and Date I. OBJECTIVES A. Content Standards B. Performance Standards C. Learning Competencie s/ Objectives (Write the LC code for each) II. CONTENT III. LEARNING RESOURCES A. References 1. Teacher’s Guide pages 2. Learner’s Materials pages 3. Textbook pages 4. Additional Learning Materials for Learning B. Other Learning Resources Grade Level Learning Area Quarter 11 MATHEMATICS 3rd The learner demonstrates understanding of key concepts of estimation of population mean and population proportion. The learner is able to estimate the population mean and population proportion to make sound inferences in real-life problems in different disciplines. Learning Competency: Identifies regions under the t-distribution corresponding to different t- values. (M11/12SP – IIIg4) Specific Objectives: At the end of the session, the learner is able to: 1. Use the t-distribution in determining the critical values. 2. Identify regions under the t-distribution that corresponds to different t-values. 3. Apply some real-life situation in the concepts learned in these lessons IDENTFYING REGIONS UNDER T-DISTRIBUTION CORRESPONDING TO T-VALUES Next Century Mathematics by Mercado, Jesus P. pp. 225 – 227, 230-231 Internet (Google) 126 IV. PROCEDURES A. Reviewing previous lesson or presenting the new lesson B. Establishing a purpose for the lesson C. Presenting examples/ instances of the new lesson 1. Using the given graph, how do we compare tscores and z-scores for a given level of confidence? 2. Describe a t-distribution. In what instances are we going to use the t-distribution in determining the confidence interval of a sample population? 3. How do we find the degrees of freedom given the population (n)? What is the use of degrees of freedom in using the tdistribution table? Group Game: Find the following critical values in the Table of t-Critical Values. Students will be provided with the Table of t-Critical Values. The teacher will flash t-values on the screen one-by-one. Three points will be given to the group with the correct answer after the given time. 1. t 0.05 for df = 8 6. t 0.10 for df = 9 2. t 0.05 for df = 25 7. t 0.01 for df = 20 3. t 0.025 for df = 15 8. t 0.01 for df = 18 4. t 0.025 for df = 27 9. t 0.025 for df = 9 5. t 0.10 for df = 12 10. t 0.025 for df = 7 A sample of size n = 20 is a simple random sample selected from a normally distributed population. Find the value of t such that the shaded area to the left of t is 0.05. D. Discussing Find the critical values of t when the area of the rightnew hand tail of the t-distribution is: concepts and a. 0.05; df = 39 practicing b. 0.10; df = 54 new skills # 1 E. Discussing new concepts and practicing new skills # 2 Suppose you have a sample of size n = 12 from a normal distribution. Find the critical value 𝑡2∝ that corresponds to a 95% confidence level. 1. What is the degree of freedom df? 2. Using the confidence level of 95%, what is ∝ ∝ and 2 ? 3. What is the critical value 𝑡2∝ ? F. Developing Mastery (Leads to Formative Using the t-distribution table. Find the degrees of freedom and the critical values of the following data. 1. n=20 at 95% confidence coefficient 2. n=10 at 99 % confidence coefficient 127 assessment 3) G. Finding practical applications of concepts and skills in daily living 3. n=12 at 95 % confidence coefficient Dana wants to know the age of all entering Grade 12 for the school year 2020-2021. The mean age of a random sample of 25 students is 18 years and standard deviation is 1.3 years. The sample comes from a normally distributed population. Use ∝ =0.1 to determine the critical value of the given data. H. Making generalizatio ns and abstractions about the lesson How to Calculate the Score for a t-Distribution I. Answer the following questions. Evaluating learning J. Additional activities for application or remediation Step 1: Subtract one from your sample size. This will be your df, or degrees of freedom. Step 2: Look up the df in the left hand side of the tdistribution table. Locate the column under your alpha level (the alpha level is usually given to you in the question. (Average Group) 1. The t distribution has degrees of freedom. 2. n b. 2 c. 10 d. n -1 3. What is the df and the critical value if n=25 at 99% confidence level (use two-tail)? 4. For a t-distribution with 25 degrees of freedom, find the values of t such that the area to the right of t is 0.05. (Advance Group) 1. Jose took a random sample of n = 12 giant squid and tracked them to calculate their mean lifespan. Their lifespans were roughly symmetric with a mean of 𝑥̅ = 4 years and a standard deviation of s = 0.5 years. He wants to use this data to construct a t interval for the mean lifespan of this type of squid with 90% confidence. What critical value 𝑡2∝ Should Jose use? 2. For a t-distribution with 14 degrees of freedom, find the values of t such that the area between – t and t is 0.90. 3. What is the critical value 𝑡2∝ for constructing a 98% confidence interval for a mean from a sample size of n = 15 observation? On Math journal: 1. After the lesson, I have learned that ________________________. 128 2. I want to clarify ____________________________________ ____. V. REMARKS VI. REFLECTION A. No. of learners who earned 80% on the formative assessment B. No. of learners who require additional activities for remediation who earned below 80% C. Did the remedial lessons work? No. of learners who have caught up with the lesson. D. No. of learners who continue to require remediation E. Which of my teaching strategies worked well? Why did this work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/ discover which I wish to share with other teachers? 129 Daily Lesson Plan in Statistics and Probability Grade 11 I. OBJECTIVES A. Content Standard B. Performance Standard C. Learning Competency/Objectives Write the LC code for each II. CONTENT III. LEARNING RESOURCES A. Reference 1. Teacher’s Guide pages 2. Learner’s Material pages 3. Textbook pages 4. Additional Materials from Learning Resource(LR) Portal B. Other Learning Resources IV. PROCEDURES A. Reviewing previous lesson or presenting the new lesson The learner demonstrates understanding of key concepts of estimation of population mean and population proportion The learner is able to estimate the population mean and population proportion to make sound inferences in real-life problems in different disciplines. The learner identifies percentiles using the t-table. M11/12SP-IIIg-5 Estimation of Parameters Statistic and Probability by Belencina, Baccay & Mateo Senior High Conceptual Math and Beyond Statistics and Probability pp.168-171 pp.138-140 https://www.dummies.com/education/math/statistics/howto-find-t-values-for-confidence-intervals/ , Manila paper, pentel pen, t-table, improvised bingo card, projector, laptop Preliminary Activity: The learners will be ask to determine whether the statement is True or False and if it is false modify the statement to make it true. 1. The shape of a normal curve is symmetrical. 2. When the confidence level is 90%, 𝛼 = 0.01 3. All confidence levels have the same confidence coefficient. 4. The confidence coefficient for a 95% confidence interval are ± 2.58. 5. The Central Limit Theorem states that as sample size increases, the shape of the distribution approximates the normal curve. Answer: 1. TRUE 2.TRUE 3. FALSE(Different) 4.FALSE (±1.96) 5.T 130 B. Establishing a purpose for the lesson C. Presenting examples/instances of the new lesson Present the objective of the lesson through Power Point Presentation Show the illustration of a Normal Distribution when the z sample size becomes small. t-for n=21 t-for n==6 D.Discussing new concepts and practicing new skills # 1 0 Start the lesson by telling the history of t-distribution originated. The t-distribution was formulated in 1908 by WS Gosset an Irish brewing employee. Discuss that t-distribution is a type of probability distribution that is similar to the normal distribution with its bell shape, but has heavier tails Explain that when 𝜎 is not known, it must be estimated by s, the sample standard deviation and when the sample size is small the critical values greater than the values for 𝑧𝛼/2 and with small sample size, more 𝑠 standard errors are needed to span the 0.95 √𝑛 confidence intervals and the tail of the normal curve becomes heavier. This number of standard error values is called t. D. Discussing new concepts and practicing new skill #2 Discuss the steps to determine the percentile of the distribution using t-table. The t-values found in the reproduced t-table are the proportion of the areas in two tails of the t-curve. Define the percentile and give examples A percentile is a number on a statistical distribution whose less-than probability is the given percentage; Example 1, The 95th percentile of the t-distribution with n – 1 degrees of freedom is that value of whose left-tail (less-than) probability is 0.95 (and whose right-tail probability is 0.05). What is a degree of freedom? A degree of freedom are the number of values that are free to vary after a sample statistic has been computed. A degree of freedom also suggest the specific curve applicable when a distribution consist of family curve. Step 1. Find the degree of freedom if n = 5 df = n-1 = 5-1 df = 4 What does this means of having a degree of freedom which is 4? 131 Answer: 4 values are free to vary and one must be a fixed value. Step 2 :Using the t-table, you look at the row for df = 4. The 95th percentile is the number where 95% of the values lie below it and 5% lie above it, so you want the right-tail area to be 0.05. Move across the row, find the column for 0.05, and you get 3.182 This is the 95th percentile of the t-distribution with 4 degrees of freedom. E. Developing mastery leads to Formative Assessment F. Finding practical application of concept and skill in daily living. To determine the percentile divide the class into three groups and distribute the worksheets, and the t-table Group 1: and Group 2 -TRIVIA Group 3. and Group 4 - BINGO The t-values found in the reproduced t-table are the proportion of the areas in two tails of the t-curve. They are critical values of t in the sense that they are the boundaries of the middle area where the true mean lies. Like the z they are also called confidence coefficient. Example: The 95th percentile of the t-distribution with 6 degrees of freedom is that value of whose left-tail (less-than) probability is 0.95 (and whose right-tail probability is 0.05). Using t-table the value is 2.447 and is located as shown in the graph. G. Making generalization and abstraction about the lesson 𝛼 = 0.05 95 % 0 2.447 Give the summary by asking the students what are the steps to determine the percentile using the t-table Step 1.Solve the degree of freedom using the formula df – n-1. Step 2. Look at the row for the degree of freedom (df) Srep3. Move across the row, and find the column for the confidence level to get the value of the percentile of the tdistribution with the degree of freedom. H. Evaluating Learning Determine the percentile using the t-table 1.The sample size n is 6 and 90% confidence level 2.The sample size n is 12 and 90% confidence level 3. The sample size n is 17 and 95% confidence level 4. The sample size n is 8 and 99% confidence level 5. The sample size n is 17 and 90% confidence level 132 Answers: 1) 2.015 2) 1.796 3)2.120 4)3.499 5)1.746 J. Additional activities for application or remediation V. REMARKS VI. REFLECTION A. No of learners who earned 80% in the evaluation B. No of learners who require additional activities for remediation who scored below 80% C. Did the remedial lessons work? No. of learners who have caught up with the lesson D. No of learners who continue to require remediation E. Which of my teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/discover which I wish to share with other teachers? 133 Group 1 TRIVIA A former military captain in the Philippines who died in the sinking of Titanic. Determine the percentile of the distribution using the t -table. A. The sample size n is 4 and 95% confidence level B. The sample size n is 8 and 95% confidence level .C.The sample size n is 11 and 90% confidence level D. The sample size n is 7 and 90% confidence level E. The sample size n is 18 and 90% confidence level F.The sample size n is 12 and 90% confidence level G.The sample size n is 14 and 99% confidence level H.The sample size n is 10 and 90% confidence level I.The sample size n is 17 and 99% confidence level J.The sample size n is 8 and 99% confidence level K.The sample size n is 13 and 95% confidence level L. The sample size n is 9 and 99% confidence level M.The sample size n is 21 and 99% confidence level N The sample size n is 3 and 95% confidence level O. The sample size n is 10 and 99% confidence level P. The sample size n is 7 and 95% confidence level R. The sample size n is 20 and 99% confidence level S The sample size n is 11 and 99% confidence level T. The sample size n is 18 and 95% confidence level U. The sample size n is 12 and 90% confidence level1. Write the letter of the correct answer in the box to find the answer 3.1 82 2.8 61 1.8 12 1.8 33 2.9 21 2.3 65 3.1 82 3.3 55 1.9 43 2.3 65 1.7 96 2.1 10 2.1 10 3.1 2.8 82 61 A R Answer: 1.8 12 C 1.8 33 H 2.9 21 I 2.3 65 B 3.1 82 A 3.3 55 L 1.9 43 D 2.3 65 B 1.7 96 U 2.1 10 T 2.1 10 T 134 Group 2 TRIVIA What was the name of the philosopher who once stated "Children today are tyrants. They contradict their parents, gobble their food, and tyrannize their teachers"? Determine the percentile of the distribution using the t -table. A. The sample size n is 4 and 95% confidence level B. The sample size n is 8 and 95% confidence level .C.The sample size n is 11 and 90% confidence level D. The sample size n is 7 and 90% confidence level E. The sample size n is 18 and 90% confidence level F.The sample size n is 12 and 90% confidence level G.The sample size n is 14 and 99% confidence level H.The sample size n is 10 and 90% confidence level I.The sample size n is 17 and 99% confidence level J.The sample size n is 8 and 99% confidence level K.The sample size n is 13 and 95% confidence level L. The sample size n is 9 and 99% confidence level M.The sample size n is 21 and 99% confidence level N The sample size n is 3 and 95% confidence level O. The sample size n is 10 and 99% confidence level P. The sample size n is 7 and 95% confidence level R. The sample size n is 20 and 99% confidence level S The sample size n is 11 and 99% confidence level T. The sample size n is 18 and 95% confidence level U. The sample size n is 12 and 90% confidence level1. Write the letter of the correct answer in the box to find the answer 3.1 3.3 2.3 1.7 2.8 2.1 1.7 2.9 4.3 3.1 2.1 1.7 2.9 82 55 65 40 61 10 40 21 03 69 10 40 21 4.3 03 Answer 3.1 82 A 3.3 55 L 2.3 65 B 1.7 40 E 2.8 61 R 2.1 10 T 1.7 40 E 2.9 21 I 135 4.3 03 N 3.1 69 S 2.1 10 T 1.7 40 E 2.9 21 I 4.3 03 N Group 3 and Group 4 BINGO Each bingo card contains 24 numbers in decimal form and a blank square, situated on a 5 by 5 grid. When the game starts, random problems are drawn in determining the percentile of the distribution using t- tables whoever of the players participating in the game completes a bingo pattern first, wins the prize (a line with five numbers in diagonal, horizontal or vertical row). Problems to be drawn in a box .1.The sample size n is 4 and 95% confidence level 2. The sample size n is 8 and 95% confidence level .3. .The sample size n is 11 and 90% confidence level 4. The sample size n is 7 and 90% confidence level 5. The sample size n is 18 and 90% confidence level 6. The sample size n is 12 and 90% confidence level 7. The sample size n is 14 and 99% confidence level 8. The sample size n is 10 and 90% confidence level 9. The sample size n is 17 and 99% confidence level 10.The sample size n is 8 and 99% confidence level 11.The sample size n is 13 and 95% confidence level 12. The sample size n is 9 and 99% confidence level 13.The sample size n is 21 and 99% confidence level 14. The sample size n is 3 and 95% confidence level 15. The sample size n is 10 and 99% confidence level 16. The sample size n is 7 and 95% confidence level 17. The sample size n is 20 and 99% confidence level 18. The sample size n is 11 and 99% confidence level 19. The sample size n is 18 and 95% confidence level 20. The sample size n is 12 and 90% confidence level 21. The sample size n is 10 and 90% confidence level 22. The sample size n is 7 and 99% confidence level 23. The sample size n is 20 and 95% confidence level 24. The sample size n is 9 and 99% confidence level 25. The sample size n is 18 and 95% confidence level 26. The sample size n is 12 and 90% confidence level 136 3.182 2.365 1.812 1.943 1.740 1.833 1.796 3.012 2.921 3.499 2.179 3.355 FREE 2.845 4.303 2.447 2.861 3.169 2.110 1.796 1.833 3.707 2.093 3.355 5.841 2.845 3.012 3.169 1.796 3.355 1.943 3.499 3.182 2.110 1.833 2.861 1.796 FREEE 1.740 3.707 1.812 2.179 2.447 2.921 4.303 3.355 2.365 1.833 5.841 2.093 3.707 1.833 5.841 1.796 2.447 2.160 2.110 1.796 2.365 3.499 1.812 3.182 FREE 3.012 2.845 3.355 2.921 2.093 3.355 1.833 2.179 2.861 1.740 4.303 3.169 137 138 School Teacher Time and Date I. OBJECTIVES A. Content Standards B. Performance Standards C. Learning Competencies/ Objectives (Write the LC code for each) Grade Level Learning Area Quarter 11 MATHEMATICS 3rd The learner demonstrates understanding of key concepts of estimation of population mean and population proportion. The learner is able to estimate the population mean and population proportion to make sound inferences in real-life problems in different disciplines. Learning Competency: Computes for the confidence interval estimate based on the appropriate form of the estimator for the population mean. (M11/12SP – IIIh- 1) Specific Objectives: At the end of the session, the learner is able to: 4. Define confidence level and confidence interval 5. Solve for the margin of error and confidence interval (interval estimate). 6. Appreciate the importance of confidence interval as one of the statistical techniques. II. CONTENT LEARNING RESOURCES A. References 5. Teacher’s Guide pages 6. Learner’s Materials pages 7. Textbook pages 8. Additional Learning Materials for Learning B. Other Learning Resources IV. PROCEDURES A. Reviewing previous lesson or presenting COMPUTING INTERVAL ESTIMATES FOR THE POPULATION MEAN III. Statistics and Probability by Belecina, Rene R., et.al. pp. 153 - 166 Internet (Google) Recall solving point estimate: “Think – Group – Share”. Using the “show me board” ask each group to give the point estimate of the following data (given will be flashed on the screen one by one). 139 the new lesson After the allotted time they will raise their answer. For every correct answer, the group will receive 2 points. 1. 4, 3.5, 3.3, 3, 3.8 2. 25, 34, 45, 30, 53, 55 3. 80, 75,86,81,77, 76, 82, 90 4. The height of the group 5. The daily allowance of the group B. Establishing a purpose for the lesson Suppose we want to know the “true” average weight of all the students in our class. Form five groups and assume that these groups are random samples. Let the students list their weights carefully. 1. What are the different ways to find the weights of the members per group? 2. What is the “true” average weight of the students? 3. How would you describe your group based on the result of the computation? 4. If you are going to enhance the precision of your guess, what is needed to be modified? 5. What is your estimate of the mean of the population where your group seems to belong? 6. Reflect on your estimation. Are you confident about it? To what extent are you confident? Express your confidence as a percentage. 7. What do we call this value (percentage or confidence)? C. Presenting examples/ instances of the new lesson Suppose we state a confidence of 95%, given that 𝑥̅ = 18, n = 50 and 𝜎 = 4 1. What is the best point estimate of the population mean? 2. What is the margin of error (E)? 3. What is the 95% confidence interval of the population mean? D. Discussing new concepts and practicing new skills # 1 Group activity: Applying the steps in calculating the interval estimates, let the students solve the following, then let them present and discuss their work in front. Average students: Sample population is normally distributed; 𝑥̅ = 42, n = 40 and 𝜎 = 3. Find the 95% confidence interval estimate for 𝜇. Advanced students: Sample population is normally distributed; n = 100, mean = 16 and population variance = 16. What is the 99% confidence interval estimate for 𝜇. 140 E. Discussing new concepts and practicing new skills # 2 K. Developing Mastery (Leads to Formative assessment 3) The mean score of a random sample of 49 Grade 11 students who took the first periodic test is calculated to be 78. The population variance is known to be 0.16. a. Find the 99% confidence interval for the mean of the entire Grade 11 students. b. Find the lower and the upper confidence limits. Solve Me! The teacher will distribute the worksheet per group with word problem and template on it. The students will brainstorm how to solve the given problem. Average students: A researcher wants to estimate the number of hours that a senior high school spend studying their lessons. A sample of 50 Grade 11 students was observed to have a mean studying time of 3 hours. The population is normally distributed with a population standard deviation of 0.5 hours. Find: a. The best point estimate of the population mean b. The 95% confidence interval of the population mean Advance students: A random selection of 40 entering Grade 11 GAS has the following GWAs (general weighted average). Assume that 𝜎 = 0.46. 96 89 86 89 93 87 89 96 97 90 87 86 90 87 86 87 97 86 90 86 86 83 98 86 87 90 87 83 89 87 87 82 83 82 98 92 86 83 89 86 Estimate the true mean GWA with 99% confidence then describe the result. L. Finding practical applications of concepts and skills in daily living Think-Pair-Share: Using the confidence levels 90%, 95%, and 99%. Let each group construct a situation or a problem consisting a mean (𝑥̅ ), number of sample (n), and population standard deviation (𝜎). Exchange this problem to other group then solve for the confidence interval. M. Making generalizations and abstractions about the lesson 1. What is a confidence level? 2. What is an interval estimate? 3. What is the computing formula for margin of error (E)? 141 4. What is the general formula for confidence intervals for large samples? 5. How do you compute the interval estimate? N. Evaluating learning Solve: You asked 50 students how satisfied they were with their track in Senior High School with a 10-point scale, with 1 = not at all satisfied and 10 = extremely satisfied. It was found out that the mean point was 7.5 with the standard deviation of 3.5. Use 90% confidence to compute the interval estimate of the population mean. O. Additional activities for application or remediation The mean and the standard deviation of the blood sugar level of randomly selected 50 patients in a hospital are 130 mg/dl and 4.6 mg/dl, respectively. a. Find the 90% confidence interval for the mean of all patients in the hospital. b. Find the lower and upper confidence limits. V. REMARKS VI. REFLECTION A. No. of learners who earned 80% on the formative assessment B. No. of learners who require additional activities for remediation who earned below 80% C. Did the remedial lessons work? No. of learners who have caught up with the lesson. D. No. of learners who continue to require remediation E. Which of my teaching strategies worked well? Why did this work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/ discover which I wish to share with other teachers? 142 School Teacher Time and Date I. OBJECTIVES A. Content Standards B. Performance Standards C. Learning Competencies/ Objectives (Write the LC code for each) II. CONTENT LEARNING RESOURCES C. References 1. Teacher’s Guide pages 2. Learner’s Materials pages 3. Textbook pages 4. Additional Learning Materials for Learning D. Other Learning Resources IV. PROCEDURES A. Reviewing previous lesson or presenting the new lesson Grade Level Learning Area Quarter 11 MATHEMATICS 3rd The learner demonstrates understanding of key concepts of estimation of population mean and population proportion. The learner is able to estimate the population mean and population proportion to make sound inferences in real-life problems in different disciplines. Learning Competency: Solves problems involving confidence interval estimation of the population mean. (M11/12SP – IIIh- 2) Specific Objectives: At the end of the session, the learner is able to: 7. Recall the steps in calculating the confidence interval 8. Solve word problems involving confidence interval estimates 9. Show perseverance and active participation during group activities SOLVING WORD PROBLEMS INVOLVING CONFIDENCE INTERVAL ESTIMATION FOR THE POPULATION MEAN III. Next Century Mathematics (Statistics & Probability for Senior High School) by Jesus P. Mercado pp. 233 – 242 Group Work: Fish bowl method. Ask a representative to pick 1 question from the bowl then discuss the answer with the group. A representative will give the idea of the group after the allotted time. a. What is an interval estimate? How does it differ from point estimate? b. What is the advantage of interval estimate over point estimate? 143 B. Establishing a purpose for the lesson c. What are the variables required in order to compute for the margin of error (E)? Give the formula. d. What are the four-step process in calculating the interval estimate? Think – group – share: Group numbers 1 & 3 to answer number 1 problem, and group numbers 2 & 4 to solve number 2. They will discuss in front their solution after the given time. 1. Given data: 99% confidence level; n=50, 𝑥̅ = 18,000 and 𝜎= 2,500. Assuming normality, use the given data to find the following: a. Margin of error b. Confidence interval for estimating the population parameter. 2. Find the minimum sample size required to estimate an unknown population mean 𝜇 using the following data: confidence level = 90%; margin of error = 0.891; 𝜎 2 = 9 C. Presenting examples/ instances of the new lesson The mean and the standard deviation of the content of a sample of 10 similar containers are 10.5 liters and 0.352, respectively. Assume that the containers are approximately normally distributed. a. Find a 95% confidence interval for the actual mean content. b. Find the lower and upper confidence limits. D. Discussing new concepts and practicing new skills # 1 Group activity: Applying the steps and formulas in calculating the confidence interval for estimating the population mean when the population variance and population standard deviation are unknown and the sample size n is less than 30 (n<30), let the students solve the following, then let them present and discuss their work in front. Average students: The following are randomly selected scores in Statistics and Probability test of twelve Grade 11 students: 75 65 76 80 85 77 81 83 80 70 71 69 a. Find a 99% confidence interval for the mean score of all grade 11 students, assuming that the students’ score is approximately normally distributed. b. Find the lower and upper confidence limits Advanced students: The following data are selected randomly from a population of normally distributed values. 36 38 43 40 46 45 46 43 47 49 44 48 47 43 51 50 52 53 54 56 a. Construct a 95% confidence interval to estimate 𝜇. b. Find the lower and the upper confidence limits. 144 E. Discussing new concepts and practicing new skills # 2 F. Developing Mastery (Leads to Formative assessment 3) Try Me! : Suppose the following data are selected randomly from a population of normally distributed values with unknown variance: 40 39 45 45 49 41 47 44 56 53 39 42 44 38 57 58 a. Compute the mean and standard deviation b. Construct a 90% confidence interval to estimate the population mean 𝜇. c. Find the lower and upper confidence limits. d. Interpret the interval. Solve Me! The teacher will let the students pick from a bowl their favorite color of candies. Students with the same color of candies will be grouped. Each group will be given a worksheet (and template) with word problem. The students will brainstorm how to solve the given problem. Yellow Group: A random sample of n = 24 data from a normal distribution with unknown variance produced 𝑥̅ = 42.5 and s = 2.6. c. Find a 90% confidence interval for the population mean. d. Interpret the interval. Red Group: A random sample of n = 19 data from a normal distribution with unknown variance produced 𝑥̅ = 32.7 and s = 2.5. a. Find a 90% confidence interval for the population mean. b. Interpret the interval. Blue Group: A random sample of n = 16 data from a normal distribution with unknown variance produced 𝑥̅ = 25.7 and s2 = 5.29. a. Find a 99% confidence interval for the population mean. b. Interpret the interval. Green Group: A random sample of n = 14 data from a normal distribution with unknown variance produced 𝑥̅ = 35.7 and s2 = 6.76. a. Find a 99% confidence interval for the population mean. b. Interpret the interval. G. Finding practical applications of concepts and skills in daily living Jeric observed that the mean age of 25 Red Cross volunteers of Sorsogon city is 18 years with standard deviation of 5 years. What is the interval estimate of the population mean? Adapt 95% confidence level. 145 H. Making generalizations and abstractions about the lesson If n<30 and 𝜎 is unknown, the confidence interval for population mean 𝜇 is : 𝑠 𝑠 𝑠 (𝑥̅ − 𝑡2∝ , 𝑥̅ + 𝑡2∝ ) 𝑜𝑟 𝑥̅ − 𝑡2∝ < 𝜇 √𝑛 √𝑛 √𝑛 𝑠 < 𝑥̅ + 𝑡2∝ √𝑛 Where: 𝑥̅ = mean of a random sample of size n n = sample size s = sample standard deviation ∝ 𝑡2∝ = t-value at (1 − ) 100% confidence level The confidence interval can be written as: ( 𝑥̅ – E , 𝑥̅ + E) or 𝑥̅ – E < 𝜇 < ̅𝑥 + E To find the margin of error (E), use the formula: 𝑠 E = 𝑡2∝ where 𝑡2∝ has n-1 2 √𝑛 I. Evaluating learning J. Additional activities for application or remediation V. VI. degrees of freedom To solve problems involving confidence interval of the population mean, the following steps should be followed: a. Find the sample mean 𝑥̅ and the sample standard deviation s (if sample mean and standard deviation is unknown) b. Find the degrees of freedom df c. Find ∝ in (1 - ∝)100% confidence level d. Find the critical value of 𝑡2∝ using the Table of tCritical Values e. Find the margin of error E f. Find the confidence interval g. Find the lower and upper confidence limits The following were scores in a General Mathematics test selected by a teacher from all the test scores of Grade 11 students. 74 78 86 88 69 83 70 83 87 62 92 66 65 75 74 90 76 57 72 83 Assume that the above scores were randomly selected by the teacher from a normal population and the variance is unknown. a. Calculate the mean and standard deviation b. Construct a 95% confidence interval to estimate the population mean score 𝑥. ̅ c. Find the lower and upper confidence limits. d. Interpret the interval. On your journal, copy and complete the following sentences: 1. I found the lesson ________. 2. I have to know more about ________________. 3. I am still confused about __________________. REMARKS REFLECTION 146 B. C. D. E. F. G. A. No. of learners who earned 80% on the formative assessment No. of learners who require additional activities for remediation who earned below 80% Did the remedial lessons work? No. of learners who have caught up with the lesson. No. of learners who continue to require remediation Which of my teaching strategies worked well? Why did this work? What difficulties did I encounter which my principal or supervisor can help me solve? What innovation or localized materials did I use/ discover which I wish to share with other teachers? 147 School Teacher Time and Date I. OBJECTIVES A. Content Standards B. Performance Standards C. Learning Competencies/ Objectives (Write the LC code for each) II. CONTENT LEARNING RESOURCES A. References 1. Teacher’s Guide pages 2. Learner’s Materials pages 3. Textbook pages 4. Additional Learning Materials for Learning B. Other Learning Resources IV. PROCEDURES A. Reviewing previous lesson or presenting the new lesson Grade Level Learning Area Quarter 11 MATHEMATICS 3rd The learner demonstrates understanding of key concepts of estimation of population mean and population proportion. The learner is able to estimate the population mean and population proportion to make sound inferences in reallife problems in different disciplines. Learning Competency: Draws conclusion about the population mean based on its confidence interval estimate. (M11/12SP – IIIh- 3) Specific Objectives: At the end of the session, the learner is able to: 10. Apply the steps in solving confidence interval estimation of the population mean 11. Describe and interpret the population mean based on its confidence interval estimate. 12. Value the importance of confidence interval as one of the statistical tool in analyzing the data. DRAWING CONCLUSION ABOUT THE POPULATION MEAN BASED ON ITS CONFIDENCE INTERVAL ESTIMATE III. Statistics and Probability by Belecina, Rene R., et.al. pp. 172 - 177 Internet (Google) Thinking Skills: By pair, let the students reflect on the different steps on how to solve problems involving confidence interval estimation of the population mean by completing the following sentences. (For advance learners, answers will not be provided. For average learners, answers can be selected from the meta strips posted on the board: 1. The parameter of interest is the ________ of the population where the sample comes from. 148 2. Specify the ______________ criteria. This information includes the ______ size and the _________; the ____ of confidence and the ______ value. 3. Collect _______ and find the ______ estimate. 4. Determine the ______ interval. Find the confidence ________ and compute the _______. Solve for the upper and lower _________, then ________ the results. Answers: 1. Mean 2. Confidence interval; sample; standard deviation; level; critical 3. Evidences; point 4. Confidence; coefficient; maximum error E; confidence limits; describe B. Establishing a purpose for the lesson (Show a picture of a farmer harvesting rice and entail a story) After applying a certain kind of fertilizer, Mang Tino harvested “palay” which yield a population standard deviation to be 4 sacks and there are 30 sacks of “palay” harvested. Find the interval estimate of the population mean per sack, using 95% confidence. 8. The parameter of interest is the _____ of the ____ where the sample comes from. 9. The ____ test is applicable to this kind of problem. 10. The level of confidence is ____ the degree of freedom is ____ and the confidence coefficients are ____. 11. The point estimate is _____. 12. The margin of error is _____. 13. The interval estimate ranges from ____ to ____. 14. The result shows that ____________________________________. C. Presenting examples/ instances of the new lesson The 15 residents of Brgy. Cambulaga attempted to add a channel on their cable TV to a list of favorites. After the task, they rated the difficulty using a 7-point scale (7 being the most difficult task). The responses are shown below: 2, 1, 3, 6, 7, 1, 2, 3, 5, 7, 2, 2, 1, 3, 2 Using the 95% confidence interval, what will be your conclusion pertaining to this result? The mean score of a random sample of 17 students who took a special test is 83.5. If the standard deviation of the scores is 4.1 and the sample comes from an approximately normal distribution, what are the point and interval estimates of the population mean adopting a confidence level of 99%. 1. What is the parameter of interest? 2. Is t-test applicable to this kind of problem? D. Discussing new concepts and practicing new skills # 1 149 3. What are the confidence level and the critical tvalues? 4. What is the maximum error(E)? 5. What is the point estimate? 6. At what values does the interval estimate ranges from? 7. What does the results tell us? E. Discussing new concepts and practicing new skills # 2 In Sorsogon provincial hospital, a sample of 10 weeks was selected and found out that the average of 10 babies were born per week. Find the 90% confidence interval of the true mean if the standard deviation of the sample was 3. Draw inferences regarding the result of the data. F. Developing Mastery (Leads to Formative assessment 3) Solve Me! The teacher will distribute the activity sheet based on the performance level of the students. This will be done by triad and the students will brainstorm how to solve the given problem. Average students: We can say with 99% confidence that the interval between 17. 33 and 18.67 contains the true mean age of the population of entering Grade 12 students based on the sample size of 25. The point estimate for the population mean is 18 years. How will you interpret the result of this problem? Advance students: A sample of 60 Grade 9 students’ ages was obtained to estimate the mean age of all grade 9 students. Mean age = 15.3 years and the population variance is 16. a. Find the 95% confidence interval for 𝜇. b. What conclusions can you make based on each estimate? G. Finding practical applications of concepts and skills in daily living H. Making generalizations and abstractions about the lesson Suppose observation on 25 chocolate bars selected from a normally distributed population yield an average weight of 200g with a standard deviation of 10 g, what is the interval estimates using 95% confidence level? Draw conclusion about the result. I. Evaluating learning How will you come up with a conclusion in a given problem? In describing the results, the statement reflects our confidence in the interval estimation process rather than the value computed from the sample data. This is because repeated application may yield different lower and upper limits of the interval. However, interval estimates are more reliable than point estimates because of the confidence coefficients associated with the range of values. This is also the reason why they are generally preferred to point estimates. Draw me close! In an interview held among 20 randomly selected senior high school students, the mean daily allowance of the students was found out to 150 J. Additional activities for application or remediation be Php20 with a standard deviation of Php3. Use 90% confidence to compute the interval estimate of the population mean. Come up with a clear and specific interpretation of the results of the data. You have learned how to compute means and standard deviations. You have also learned how to estimate the population mean 𝜇. Do you think that the t-test is a versatile test in the sense that it may be used for both small and large samples? Explain your answer V. REMARKS VI. REFLECTION A. No. of learners who earned 80% on the formative assessment B. No. of learners who require additional activities for remediation who earned below 80% C. Did the remedial lessons work? No. of learners who have caught up with the lesson. D. No. of learners who continue to require remediation E. Which of my teaching strategies worked well? Why did this work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/ discover which I wish to share with other teachers? 151 School Teacher Time and Date I. OBJECTIVES A. Content Standards B. Performance Standards C. Learning Competencies/ Objectives II. CONTENT III. LEARNING RESOURCES A. References 1. Teacher’s Guide Pages 2. Learner’s Material Pages 3. Textbook Pages 4. Additional Materials from Learning Resources B. Other Learning Resources IV. PROCEDURES A. Reviewing previous lesson or presenting the new lesson Grade Level Learning Area Quarter 11 MATHEMATICS 3rd The learner demonstrates understanding of key concepts of estimations of population mean and population proportion. The learner is able to estimate the population mean and population proportion to make sound inferences in real-life problems in different disciplines. 1. The learner identifies point estimator for the population proportion. (M11/12SP-IIIi-1) 2. The learner computes for the point estimate of the population proportion. (M11/12SP-IIIi-2) Estimation of Parameters Statistics and Probability 344-346 1. Statistics and Probability 146-151 2. Statistics and Probability by Danilo De Guzman pages 133-135 Activity: Jason noted that every weekend, a group of athletes jog in a nearby park. On a particular day, he observed that there were 20 runners and that 8 of them were female. He observed the joggers for five weeks, noting their number and their gender. Fill-in the blanks in the table to complete the data and answer question below: Week 1st 2nd 3rd 4th 5th Male 12 12 10 Female 8 10 6 15 Total 20 26 20 Guide Question: What proportions of runners are female a. in fraction form? b. in decimal form? c. in percentage form? 152 B. Establishing a purpose for the lesson Solution: To determine the proportion of the female runners, simply compute as follows: Week 1st 2nd 3rd 4th 5th Male 12 16 12 10 9 Female 8 10 6 10 15 Total 20 26 18 20 24 8 10 6 10 15 Proportion 20 26 18 20 24 Decimal 0.4 0.38 0.33 0.5 0.625 Percentag 40% 38% 33% 50% 62.5% e C. Presenting examples/instances of the new lesson The percentage expression 40% is also called a proportion. Percentages are commonly used when reporting frequencies of subsets of populations. In computing, percentages are first converted to proportions in decimal form. Proportions represent probabilities. If Jason makes a probability statement that all joggers in the park on the first week are female, he may report 40% or 0.40. D. Discussing new concepts and practicing new skill #1 We denote 𝑝 as the population proportion and 𝑝̂ “p hat” as the point estimate of sample proportion. 𝒙 ̂ = , where 𝑥 is the number The formula is 𝒑 𝒏 of sample elements that possess the desired characteristics and 𝑛 is the sample size. Example 1: If 350 students from the graduates of a batch were surveyed and 30 of them answered that they took up BS Mechanical Engineering (BSME), what is the estimated proportion of those who took up BS ME out of the whole batch? Solution: Let 𝑝̂ as the sample proportion of BSME graduates, 𝑥=30 (number of BS ME graduates), and 𝑛=350 (total number of surveyed graduates). 𝑥 30 𝑝̂ = = = 0.086 or 8.6% 𝑛 E. Discussing new concepts and practicing new skill #2 350 We denote 𝑞 as the sample proportion of “not 𝑝”, and 𝑞̂ “q hat” as the point estimate of proportion of “not 𝑝”. ̂ =𝟏− 𝒑 ̂ The formula is 𝒒 Example 2: From example 1, what is the estimated proportion of graduates who didn’t take up BSME? 153 Solution: Let 𝑞̂ as the sample proportion of non-BSME graduates. 𝑞̂ = 1 − 𝑝̂ = 1 − 0.086 = 0.914 or 91.4% F. Developing mastery (Leads to Formative Assessment) G. Finding practical applications of concepts and skills in daily living Firm Up: Find 𝑝̂ and 𝑞̂, given 𝑥 and 𝑛. a. 𝑥 = 56 ; 𝑛 = 80 b. 𝑥 = 35 ; 𝑛 = 96 c. 𝑥 = 420 ; 𝑛 = 1000 Answers: a. 𝑝̂ = 0.7 or 70% ; 𝑞̂ = 0.3 or 30% b. 𝑝̂ = 0.364 or 36.4% ; 𝑞̂ = 0.636 or 63.6% c. 𝑝̂ = 0.42 or 42% ; 𝑞̂ = 0.58 or 58% Restaurants regularly ask customers to accomplish questionnaires on the kind of service that their staff renders. Suppose 1 200 people are randomly chosen from a target population and are asked if they like the services of a specific restaurant. There are 908 respondents who like the service. What is the estimate of true proportion of all customers who like the service of the restaurant? Solution: Let 𝑝 the population proportion. We can estimate 𝑝 by computing 𝑝̂ = 𝑁𝑜. 𝑜𝑓 𝑐𝑢𝑠𝑡𝑜𝑚𝑒𝑟𝑠 𝑤ℎ𝑜 𝑙𝑖𝑘𝑒 𝑡ℎ𝑒 𝑠𝑒𝑟𝑣𝑖𝑐𝑒 𝑁𝑜. 𝑜𝑓 𝑝𝑒𝑜𝑝𝑙𝑒 𝑠𝑎𝑚𝑝𝑙𝑒𝑑 So, 𝑝̂ = 908 1200 = 0.757 Only 76% of all customers like the services of the restaurant. The owner might want to improve the service to increase the revenue of the restaurant. H. Making generalizations and abstractions about the lesson A point estimate is a single value used to approximate a population parameter. ̂= The point estimator of sample population is 𝒑 𝒙 ̂ =𝟏− 𝒑 ̂ as the estimator of “not 𝑝̂ ”. , and 𝒒 𝒏 154 I. Evaluating Learning 1. What is the point estimator of the population proportion? 2. Nora conducted a survey for a fast food restaurant owner who wanted to know the level of acceptability (Acceptable or Not Acceptable) of a new food combo among customers. There were 182 respondents found the new food combo was acceptable. If there were 256 in the sample, what is 𝑝̂ and 𝑞̂ ? Answer: 𝑥 1. 𝑝̂ = 𝑛 2. a. There are 182 who find the new food combo acceptable. In terms of proportion: 𝑥 182 𝑝̂ = = = 0.71 = 71% 𝑛 256 2. b. There are 74 who find the new food combo not acceptable. This proportion is 𝑞̂ = 1 − 𝑝̂ = 1 − 7.1 = 0.289 = 28.9% or 29% J. Additional activities for application or remediation V. REMARKS VI. REFLECTION A. No. of learners who earned 80% in the evaluation B. No. of leaners who require additional activities for remediation who scored below 80% C. Did the remedial lessons work? No. of learners who have caught up with the lesson D. No. of leaners who continue to require remediation E. Which of my teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal or supervisor can help me solve? 155 G. What innovation or localized materials did I use/discover which I wish to share with other teachers? 156 School Teacher Time and Date I. OBJECTIVES A. Content Standards B. Performance Standards C. Learning Competencies/ Objectives II. CONTENT III. LEARNING RESOURCES C. References 1. Teacher’s Guide Pages 2. Learner’s Material Pages 3. Textbook Pages 4. Additional Materials from Learning Resources D. Other Learning Resources IV. PROCEDURES A. Reviewing previous lesson or presenting the new lesson Grade Level Learning Area Quarter 11 MATHEMATICS 3rd The learner demonstrates understanding of key concepts of estimations of population mean and population proportion. The learner is able to estimate the population mean and population proportion to make sound inferences in real-life problems in different disciplines. 3. The learner identifies the appropriate form of the confidence interval estimator for the population proportion based on Central Limit Theorem. (M11/12SP-IIIi-3) 4. The learner computes for the confidence interval estimate of the population proportion. (M11/12SPIIIi-4) Estimation of Parameters Statistics and Probability 346-348 1. Statistics and Probability 146-151 2. Statistics and Probability by Danilo De Guzman pages 134-138 Review the previous lesson. If 350 students from the graduates of a batch were surveyed and 30 of them answered that they took up BS Mechanical Engineering (BSME), what is the estimated proportion of those who took up BS ME out of the whole batch? Solution: 𝑥 30 a. 𝑝̂ = = = 0.086 or 8.6% 𝑛 350 b. 𝑞̂ = 1 − 𝑝̂ = 1 − 0.086 = 0.914 or 91.4% Hence, the point estimate of the population proportion of those who took up BSME out of the whole batch is 0.086 or 8.6%. 157 B. Establishing a purpose for the lesson Estimates about a population proportion may be made just like estimates of the population mean. Just like means, we can also form confidence intervals about the population proportion. C. Presenting examples/instances of the new lesson If 350 students from the graduates of a batch were surveyed and 30 of them answered that they took up BS Mechanical Engineering (BSME), construct 90% confidence interval for the estimated proportion of those who took up BS ME out of the whole batch? D. Discussing new concepts and practicing new skill #1 Solution: 30 Step 1: Given 𝑥 = 30, and 𝑛 = 350, 𝑝̂ = = 350 0.086. Thus, 𝑞̂ = 1 − 𝑝̂ = 0.914. Step 2: Since 𝑛𝑝̂ and 𝑛𝑞̂ are greater than 5, and 𝑛 ≥ 30, the sample size is normally distributed (according to Central Limit Theorem). Thus, use the confidence interval estimate: 𝑝̂ 𝑞̂ 𝑝̂ 𝑞̂ 𝑝̂ − 𝑧𝛼 √ < 𝑝 < 𝑝̂ + 𝑧𝛼 √ 𝑛 𝑛 2 2 Step 3: Recall that for a confidence level of 90%, 𝛼 = 10% and 𝑧𝛼 = 1.645 (use z-table). 2 Step 4: Substituting the given values, we get: 0.086−1.645√ (0.086)(0.914) 350 0.086+1.645√ <𝑝< (0.086)(0.914) 350 Step 5: With 90% confidence, we state that the interval estimate from 0.061 to 0.111 or 6.1% to 11.1% contains the true percentage of graduates of a batch who answered that they took up BS Mechanical Engineering (BSME). 158 E. Discussing new concepts and practicing new skill #2 To check if the confidence interval estimate is true, we let: 𝑝̂𝑞̂ 𝑛 as the lower boundary, and 𝑝̂𝑞̂ 𝑛 as the upper boundary. 𝑝̂ − 𝑧𝛼 √ 2 𝑝̂ + 𝑧𝛼 √ 2 Then, get the average of the lower and upper boundaries as shown below: 𝐿𝐵+𝑈𝐵 𝑝̂ = 2 0.061+ 0.111 = 2 𝑝̂ = 0.086 It shows that 𝑝̂ = 0.086 or 8.6% lies between the confidence interval estimate from 0.061 to 0.111 or 6.1% to 11.1%. F. Developing mastery (Leads to Formative Assessment) Firm Up: Compute the confidence interval of the population proportion given 𝑛, 𝑝̂ , and the confidence level. a. 𝑛 = 210, 𝑝̂ = 0.60, 95% b. 𝑛 = 460, 𝑝̂ = 0.53, 90% c. 𝑛 = 678, 𝑝̂ = 0.28, 99% Use this table as reference for confidence interval calculation. Confidence Critical (𝑧) Level value 50% 0.67449 75% 1.15035 90% 1.64485 95% 1.95996 97% 2.17009 99% 2.57583 99.9% 3.29053 G. Finding practical applications of concepts and skills in daily living Answers: a. from 0.534 to 0.666 or 53.4% to 66.6% b. from 0.492 to 0.568 or 49.2% to 56.8% c. from 0.235 to 0.324 or 23.5% to 32.4% In a survey of 500 random households in a particular village, mothers have been asked if they use cell phones to communicate. There are 376 who have said YES. Use a 95% confidence to estimate the proportion of all mothers who use the cell phone to communicate. Solution: 159 376 Step 1: Given 𝑥 = 376, and 𝑛 = 500, 𝑝̂ = = 500 0.752. Thus, 𝑞̂ = 1 − 𝑝̂ = 0.248. Step 2: Since 𝑛𝑝̂ and 𝑛𝑞̂ are greater than 5, and 𝑛 ≥ 30, the sample size is normally distributed (according to Central Limit Theorem). Thus, use the confidence interval estimate: 𝑝̂ 𝑞̂ 𝑝̂ 𝑞̂ 𝑝̂ − 𝑧𝛼 √ < 𝑝 < 𝑝̂ + 𝑧𝛼 √ 𝑛 𝑛 2 2 Step 3: Recall that for a confidence level of 95%, 𝛼 = 5% and 𝑧𝛼 = 1.96 (use z-table). 2 Step 4: Substituting the given values, we get: (0.752)(0.248) 500 0.752−1.96√ <𝑝< (0.752)(0.248) 0.752+1.96√ H. Making generalizations and abstractions about the lesson 500 Step 5: With 95% confidence, we state that the interval estimate from 0.714 to 0.79 or 71.4% to 79% contains the true percentage of households in a particular village that uses cell phones to communicate. Since 𝑛𝑝̂ and 𝑛𝑞̂ are greater than 5, and 𝑛 ≥ 30, the sample size is normally distributed (according to Central Limit Theorem). Thus, use the confidence interval estimate: 𝑝̂ 𝑞̂ 𝑝̂ 𝑞̂ 𝑝̂ − 𝑧𝛼 √ < 𝑝 < 𝑝̂ + 𝑧𝛼 √ 𝑛 𝑛 2 2 Then, to check if the confidence interval estimate is true get the average of the lower and upper boundaries as shown below: 𝐿𝐵 + 𝑈𝐵 𝑝̂ = 2 I. Evaluating Learning 1. What is the confidence interval estimator for the population proportion based on Central Limit Theorem? 2. Nora conducted a survey for a fast food restaurant owner who wanted to know the level of acceptability (Acceptable or Not Acceptable) of a new food combo among customers. Get the 97% confidence interval that 182 respondents found the new food combo was acceptable if there were 256 in the sample. Answer: 𝑝̂𝑞̂ 𝑛 1. 𝑝̂ − 𝑧𝛼 √ 2 𝑝̂𝑞̂ 𝑛 < 𝑝 < 𝑝̂ + 𝑧𝛼√ 2 2. With 97% confidence, we state that the interval estimate from 0.648 to 0.772 or 64.8% to 77.2% contains the true percentage of respondents who found the new food combo was acceptable. 160 J. Additional activities for application or remediation V. REMARKS VI. REFLECTION A. No. of learners who earned 80% in the evaluation B. No. of leaners who require additional activities for remediation who scored below 80% C. Did the remedial lessons work? No. of learners who have caught up with the lesson D. No. of leaners who continue to require remediation E. Which of my teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/discover which I wish to share with other teachers? 161 Daily Lesson Plan in Statistics and Probability Grade 11/12 Quarter 3 Week 9 I. OBJECTIVES A. Content Standard B. Performance Standard C. Learning Competency/Objectives II. CONTENT The learner demonstrates understanding of key concepts of estimation of population mean and population proportion. The learner is able to estimate the population mean and population proportion to make sound inferences in real-life problems in different disciplines. The learner solves problems involving confidence interval estimation of the population proportion. M11/12SP-IIIi-5 Problem Solving on Confidence Interval Estimation of Population Proportion III. LEARNING RESOURCE References Statistics and Probability by Belencina, Baccay & Mateo pp. 195-199 Other Learning Resource Manila paper, calculator, permanent markers IV. PROCEDURES A. Reviewing previous This activity can be done orally, or given as a lessons or presenting written task which can be accomplished either the new lesson individually, dyad, triad, or in a small group. A. Compute 𝑞̂ given 𝑝̂ . (Note that 𝑞̂ = 1 − 𝑝̂ ) a. 𝑝̂ = 0.02 (Answer: 𝑞̂ = 0.98) b. 𝑝̂ = 0.50 (Answer: 𝑞̂ = 0.50) c. 𝑝̂ = 0.80 (Answer: 𝑞̂ = 0.20) d. 𝑝̂ = 0.62 (Answer: 𝑞̂ = 0.38) e. 𝑝̂ = 0.60 (Answer: 𝑞̂ = 0.40) 𝑋 B. Find 𝑝̂ , the point estimate 𝑝. (Note that 𝑝̂ = ) 𝑛 1. X = 12; n = 30 ( Answer: 𝑝̂ =0.4) 2. X = 111; n = 300 ( Answer: 𝑝̂ =0.37) 3. X = 250; n = 500 ( Answer: 𝑝̂ =0.50) 4. X = 360; n = 900 ( Answer: 𝑝̂ =0.4) 5. X = 150; n = 600 ( Answer: 𝑝̂ =0.25) C. Determine the 𝑍𝛼 given the following 2 confidence level. 1. 90% (Answer: 𝑍𝛼=1.64) 2 2. 95% (Answer: 𝑍𝛼=1.96) 3. 97% (Answer: 𝑍𝛼=2.17) 4. 98% (Answer: 𝑍𝛼=2.33) 5. 99% (Answer: 𝑍𝛼=2.58) 2 2 2 2 Note: For slow learners, give only 2 items in Parts A and B while. 162 D. Establishing a purpose for the lesson Inform the learners that throughout the lesson, they will be asked to solve word problems involving confidence interval estimation of population proportion. Inform the learners of the steps in solving word problem that they can use later on while solving word problems. E. Presenting Examples/Instances of the Lesson Step 1. Describe the population parameter of interest Step 2. Specify the confidence Interval Criteria a. Check the assumptions b. Determine the test statistic to be used to calculate the interval c. State the level of confidence Step 3. Collect and preset sample evidence a. Collect the sample information. b. Find the point estimate Step 4. Compute the interval estimate a. Find 𝑞̂. b. Find the maximum error E. c. Find the limits. d. Describe the results. Present the problem below to the learners. In a graduate teacher college, a survey was conducted to determine the proportion of students who want to major in Science. If 368 out of 850 students said Yes, with 95% confidence, what interpretation can we make regarding the probability that all students in the teacher graduate college want to major in Science? After presenting the word problem, the learners will be grouped into small groups with a minimum of 45 learner in every group to solve the given problem. Provide the learners will materials such as manila paper and permanent markers. Learners may use calculators in doing this task. F. Discussing New concepts and Practicing New Skills # 1 The learners will be asked to post their outputs and share their solution to the class. (Note: If there are groups which arrived at the same answer, choose only one from among this groups to present the output.) The learners should be able to arrive at the following answer. Steps Describe the population parameter of interest 163 Solution The parameter of interest is the mean proportion p of all students in the teacher graduate college who want to major in Science. Specify the confidence Interval Criteria 1. Check the By CLT, the sample assumptions size of 850 is normally distributed. 2. Determine the test statistic to The test statistic is the be used to p. calculate the interval 3. State the level of confidence Confidence level: 95% and α = 0.05 Confidence coefficient = 1.96 Collect and preset sample evidence 1. Collect the X = 368 and n=850. sample information. 2. Find the point 𝑝̂ = 𝑋 = 368 = 0.432 ≈ 𝑛 850 estimate 0.43 The point estimate of the population is 0.43. Compute the interval estimate 1. Find q ̂. 𝑞̂= 1-𝑝̂ = 1 – 0.43 = 0.57 2. Find the maximum error 𝑝̂𝑞̂ (0.43)(0.57) √ = √ = E. 𝑛 850 0.017 3. Find the limits. For the lower limit 𝑝̂𝑞̂ 𝑛 𝑝̂ - 𝑍𝛼 √ 2 =0.43 – 1.96(0.017) =0.43 – 0.034 = 0.396 or 39.6% For the upper limit 𝑝̂ + 𝑍𝛼 √ 2 𝑝̂𝑞̂ 𝑛 =0.43 + 1.96(0.017) = 0.463 or 46.4% 164 Describe the results. Thus, with 95% confidence, we can assert that the interval from 39.6% to 46.4% contains the true percentage of all graduate students who want to major in Science. For slow and average learners, a guided worksheet may be used. (see Attached Practice Exercise 1). G. Developing Mastery This task will be accomplished individually. Problem: In a certain food stall, 278 out of 500 randomly selected consumers indicate their preference for new kind of food combination. Use 99% confidence interval to estimate the true proportion p who like new food combination. Distribute Practice Exercise 2. (see attached) Practice Exercise 2A for slow and average learners and Practice Exercise 2B for advanced learners. H. Making generalization and abstraction about the lesson What are the steps in solving word problems involving confidence interval estimation of population proportion? I. What are the essential formulae/formulas that we need to solve this types of problems? For Slow learners, distribute Worksheet 1. Evaluating Learning For average and advance learners, distribute Worksheet 2. 165 Practice Exercise 1 Problem. In a graduate teacher college, a survey was conducted to determine the proportion of students who want to major in Science. If 368 out of 850 students said Yes, with 95% confidence, what interpretation can we make regarding the probability that all students in the teacher graduate college want to major in Science? Steps Solution Describe the population parameter of The parameter of interest is the mean interest proportion p of all students in the teacher graduate college who want to major in Science. Specify the confidence Interval Criteria By CLT, the sample size of 850 is 1. Check the assumptions normally distributed. 2. Determine the test statistic to be used to calculate the interval 3. State the level of confidence Collect and preset sample evidence 1. Collect the sample information. 2. Find the point estimate The test statistic is the p. Confidence level: 95% and α = 0.05 Confidence coefficient = _______ X = 368 and n=850. 𝑝̂ = 𝑋 𝑛 = 368 850 = ________ The point estimate of the population is ___. Compute the interval estimate 1. Find q ̂. 2. Find the maximum error E. 3. Find the limits. 𝑞̂= 1-𝑝̂ = 1 – 0.43 = _______ 𝑝̂𝑞̂ 𝑛 √ (0.43)(0.57) = 850 =√ _______ For the lower limit 𝑝̂𝑞̂ 𝑛 𝑝̂ - 𝑍𝛼 √ 2 =0.43 – 1.96(0.017) =0.43 – _______ = __________ For the upper limit 𝑝̂ + 𝑍𝛼 √ 2 Describe the results. 𝑝̂𝑞̂ 𝑛 =0.43 + 1.96(0.017) = 0.43 + _______ = _________ Thus, with 95% confidence, we can assert that the interval from ____% to ____% contains the true percentage of all graduate students who want to major in Science. 166 Practice Exercise 2A Problem: In a certain food stall, 278 out of 500 randomly selected consumers indicate their preference for new kind of food combination. Use 99% confidence interval to estimate the true proportion p who like new food combination. Steps Solution Describe the population parameter of The parameter of interest is the mean interest proportion p of ____________________ Specify the confidence Interval Criteria 1. Check the assumptions 2. Determine the test statistic to be used to calculate the interval 3. State the level of confidence Collect and preset sample evidence 1. Collect the sample information. 2. Find the point estimate By CLT, the sample size of _____ is normally distributed. The test statistic is the p. Confidence level: 99% and α = 0.01 Confidence coefficient = _______ X = 278 and n=500 𝑋 𝑝̂ = = = ________ (round to the nearest Thousandths) 𝑛 The point estimate of the population is ___. Compute the interval estimate 1. Find q ̂. 2. Find the maximum error E. 3. Find the limits. 𝑞̂= 1-𝑝̂ = 1 – ______ = _______ 𝑝̂𝑞̂ 𝑛 √ ( =√ )( 500 ) = _______ For the lower limit 𝑝̂𝑞̂ 𝑝̂ - 𝑍𝛼 √ 2 𝑛 =0.556 – 2.58(______) =0.556 – _______ = __________ For the upper limit 𝑝̂ + 𝑍𝛼 √ 2 Describe the results. 𝑝̂𝑞̂ 𝑛 =0.556 + 2.58(_____) = 0.556 + _______ = _________ Thus, with 99% confidence, we can assert that the interval from ____% to ____% contains the true proportion of all consumers who like the new food combination. 167 Practice Exercise 2B Problem: In a certain food stall, 278 out of 500 randomly selected consumers indicate their preference for new kind of food combination. Use 99% confidence interval to estimate the true proportion p who like new food combination. Steps Describe the population parameter of interest Solution Specify the confidence Interval Criteria 4. Check the assumptions 1. Determine the test statistic to be used to calculate the interval 2. State the level of confidence Collect and preset sample evidence 1. Collect the sample information. 2. Find the point estimate Compute the interval estimate 1. Find q ̂. 2. Find the maximum error E. 3. Find the limits. Describe the results. Thus, with 99% confidence, we can assert that the interval from ____% to ____% contains the true proportion of all consumers who like the new food combination. 168 Worksheet 1 Problem: In a survey, 1000 Grade 7 students were asked if they read storybooks. There were 318 who said Yes. Use 95% confidence interval to determine the population proportion p of all grade 7 students who read story books. Steps Solution Describe the population parameter of The parameter of interest is the mean interest proportion p of all Grade 7 students who read story books. Specify the confidence Interval Criteria By CLT, the sample size of 1000 is 1. Check the assumptions normally distributed. The test statistic is the p. 2. Determine the test statistic to be used to calculate the interval Confidence level: 95%, α = 0.05. Confidence coefficient: _________ 3. State the level of confidence Collect and preset sample evidence 1. Collect the sample information. X = _______ n =1000 2. Find the point estimate 𝑋 𝑝̂ = = = ___________ 𝑛 The point estimate of the population proportion is ___________ Compute the interval estimate 1. Find q ̂. 𝑞̂= 1-𝑝̂ = 1 – ______ = _______ 2. Find the maximum error E. 𝑝̂𝑞̂ 𝑛 √ ( )( 500 =√ ) = _______ 3. Find the limits. For the lower limit 𝑝̂𝑞̂ 𝑛 𝑝̂ - 𝑍𝛼 √ 2 = _______ – 1.96(______) =_______ – _______ = __________ For the upper limit 𝑝̂ + 𝑍𝛼 √ 2 𝑝̂𝑞̂ 𝑛 = _______ + 1.96(______) =_______ + _______ = __________ Describe the results. Thus, with 99% confidence, we can assert that the interval from ____% to ____% contains the true proportion of all Grade 7 students who read story books. 169 Worksheet 1 Problem: In a survey, 1000 Grade 7 students were asked if they read storybooks. There were 318 who said Yes. Use 95% confidence interval to determine the population proportion p of all grade 7 students who read story books. Steps Solution Describe the population parameter of The parameter of interest is the mean interest proportion p of all Grade 7 students who read story books. Specify the confidence Interval Criteria By CLT, the sample size of 1000 is 4. Check the assumptions normally distributed. The test statistic is the p. 5. Determine the test statistic to be used to calculate the interval Confidence level: 95%, α = 0.05. Confidence coefficient: _________ 6. State the level of confidence Collect and preset sample evidence 3. Collect the sample information. X = _______ n =1000 4. Find the point estimate 𝑋 𝑝̂ = = = ___________ 𝑛 The point estimate of the population proportion is ___________ Compute the interval estimate 4. Find q ̂. 𝑞̂= 1-𝑝̂ = 1 – ______ = _______ 5. Find the maximum error E. 𝑝̂𝑞̂ 𝑛 √ ( )( 500 =√ ) = _______ 6. Find the limits. For the lower limit 𝑝̂𝑞̂ 𝑛 𝑝̂ - 𝑍𝛼 √ 2 = _______ – 1.96(______) =_______ – _______ = __________ For the upper limit 𝑝̂ + 𝑍𝛼 √ 2 𝑝̂𝑞̂ 𝑛 = _______ + 1.96(______) =_______ + _______ = __________ Describe the results. Thus, with 99% confidence, we can assert that the interval from ____% to ____% contains the true proportion of all Grade 7 students who read story books. 170 School Teacher Time and Date I. OBJECTIVES A. Content Standards B. Performance Standards C. Learning Competencies/ Objectives II.CONTENT III. LEARNING RESOURCES A. References 1. Teacher’s Guide 2. Learner’s Materials Page 3. Textbook Pages IV.PROCEDURES A. Reviewing previous lesson or motivation Grade Level Learning Area Quarter 11 MATHEMATICS 3rd The learner demonstrates understanding of key concepts of tests of hypotheses on the population mean and population proportion The learner is able to perform appropriate tests of hypotheses involving the population mean and population proportion to make inferences in real-life problems in different disciplines. M11/12SP-IVa-1 Formulates the appropriate null and alternative hypotheses on a population mean. The learner illustrates (a) null hypothesis (b) alternative hypothesis and (c) types of errors in hypothesis testing. Tests of Hypothesis Commission on Higher Education and Philippine Normal University (2016). Teaching Guide for Senior High School: Statistics and Probability. pp 375-378 Belecina, R. R.,Baccay E. S.,Mateo E. B. Statistics and Probability pp 216-225 Ask a students to react on the government pronouncement about El Niño phenomenon. Describe the El Niño phenomenon and its possible consequences further. “The country will experience El Niño phenomenon in the next few months.” Write learners’ reactions on the board. Their reactions may include the following: 1. The occurrence of El Niño phenomenon is not sure. 2. There is a possibility that El Niño phenomenon may not occur. 3. The effects of El Niño phenomenon are devastating to the country. 4. Some of the consequences of the El Niño phenomenon are tolerable while other consequences are not. 5. The validity of the statement could be tested based on some empirical facts 171 B. Establishing a purpose for the lesson How can you determine if your conjecture is either true or false? What is your basis in making decisions? In decision-making, we usually follow certain processes; weigh alternatives, collect evidence and make a decision. After a decision is made, an appropriate interpretation is made (or an action is undertaken). We follow these basic processes in testing hypothesis in statistics. C. Presenting examples/ instances of the new lesson Discuss the results of the motivational activity with emphasis on the following points: A statistical hypothesis is a claim or a conjecture that may either be true or false There are two possible actions that one can do with the statement. These actions are either to accept the statement or to reject it The degree of the possible consequence is the basis in making the decision. If the consequences of accepting the claim that El Niño phenomenon is going to happen are tolerable, then we may not reject the pronouncement. However, if the consequences are severe, then we reject the claim. D. Discussing new concepts and practicing new skills #1 A test of hypothesis is a procedure based on a random sample of observations with a given level of probability of committing an error in making the decision, whether the hypothesis is true or false. There are two kinds of a statistical hypothesis: the null and the alternative hypothesis. • Null hypothesis -Denoted by Ho -This is a statement or claim or conjecture to be tested • Alternative hypothesis - Denoted by Ha - the claim that is accepted in case the null hypothesis is rejected The null and alternative hypotheses are complementary and must not overlap. The usual pairs are as follow: a. Ho: Parameter = Value versus Ha: Parameter ≠ Value; b. Ho: Parameter = Value versus Ha: Parameter < Value; c. Ho: Parameter = Value versus Ha: Parameter > Value; 172 d. Ho: Parameter ≤ Value versus Ha: Parameter > Value; and e. Ho: Parameter ≥ Value versus Ha: Parameter < Value Example: Consider the average number of text messages that a Grade 11 student sends in a day. The statement could be stated as follows: “The average daily number of text messages that a Grade 11 student sends is equal to 100.” • The statement “The average daily number of text messages that a Grade 11 student sends is equal to 100” is considered as the Null hypothesis(Ho) • The statement “The average daily number of text messages that a Grade 11 student sends is not equal to 100” is the alternative statement(Ha) E. Discussing new concepts and practicing new skills #2 Types of error in hypothesis testing Type I error - an error is committed when we reject a true hypothesis Type II error - an error is committed when we fail to reject (accept) a false hypothesis Action Reject the hypothesis Fail to reject(Accept) the hypothesis Hypothesis is TRUE Error Committed No Error Committed Hypothesis is FALSE No Error Committed Error Committed Example: Alden is exclusively dating Maine. He remembers that on their first date, Maine told him that her birthday was this month. However, he forgot the exact date. Ashamed to admit that he did not remember, he decides to use hypothesis testing to make an educated guess that today is Maine’s birthday. Help Alden do it. Answer: • The null hypothesis can be stated as Ho: Today is Maine’s birthday while the alternative hypothesis is Ha: Maine’s birthday is on another day and not today. • Type I error is committed when Alden’s guess of Maine’s birthday is not on this day and a possible consequence is that Alden failed to greet or give Maine a birthday gift today. 173 F. Developing mastery (Leads to Formative Assessment 3) • On the other hand, Type II error is committed when Alden guessed that today is Maine’s birthday. A possible consequence of this Type II error is that Alden made the mistake of greeting Maine a happy birthday on that day. Group Activity The class will be divided into 4 groups. Provide each group with the materials needed in accomplishing the tasks as manila paper, pentel pen and hand out. Direction: Formulate the appropriate null and alternative hypotheses and identify situations where Type I and Type II errors are committed. Have them state its possible consequences. Group 1 A manufacturer of IT gadgets recently announced they had developed a new battery for a tablet and claimed that it has an average life of at least 24 hours. Would you buy this battery? Answer: The null hypothesis can be stated as Ho: The average life of the newly developed battery for a tablet is at least 24 hours while the alternative hypothesis is Ha: The average life of the newly developed battery for a tablet is less than 24 hours. Type I error is committed when you did not buy the battery and a possible consequence is you lost the opportunity to have a battery that could last for at least 24 hours. On the other hand, Type II error is committed when you did buy the battery and found out later that the battery’s life was less than 24 hours. A possible consequence of this Type II error is that you wasted your money in buying the battery. Group 2 A teenager who wanted to lose weight is contemplating on following a diet she read about in the Facebook. She wants to adopt it but, unfortunately, following the diet requires buying nutritious, low calorie yet expensive food. Help her decide. Answer: The null hypothesis can be stated as Ho: The diet will not result to a change in her weight while the alternative hypothesis is Ha: The diet will induce a reduction in her weight. Type I error is committed when the teenager did follow the diet and a possible consequence is that she spent unnecessarily for a diet that did not help her reduce weight. On the other hand, Type II error is committed when the teenager did not follow the diet. A possible consequence of this Type II error is that the teenager lost the opportunity to attain her goal of weight reduction. 174 Group 3 After senior high school, Lily is pondering whether or not to pursue a degree in Statistics. She was told that if she graduates with a degree in Statistics, a life of fulfilment and happiness awaits her. Assist her in making a decision. Answer: The null hypothesis can be stated as Ho: Life of fulfillment and happiness awaits her after obtaining a degree in Statistics while the alternative hypothesis is Ha: Life of fulfillment and happiness does not happen after obtaining a degree in Statistics. Type I error is committed when Lily does not pursue a degree in Statistics and a possible consequence is that she’ll miss the promised life of fulfilment and happiness after obtaining a degree in Statistics. On the other hand, Type II error is committed when Lily decides to obtain a degree in Statistics. A possible consequence of this Type II error is that Lily will miss the opportunity to experience a life of fulfilment and happiness after obtaining a degree in Statistics. Group 4 An airline company regularly does quality control checks on airplanes. Tire inspection is included since tires are sensitive to the heat produced when the airplane passes through the airport’s runway. The company, since its operation, uses a particular type of tire which is guaranteed to perform even at a maximum surface temperature of 107oC. However, the tires cannot be used and need to be replaced when surface temperature exceeds a mean of 107oC. Help the company decide whether or not to do a complete tire replacement. Answer: The null hypothesis can be stated as Ho: The surface temperature of the tires is at most 107 oC while the alternative hypothesis is Ha: The surface temperature of the tires is greater than 107 oC. Type I error is committed when the airline company orders a tire replacement when in fact it is not needed. A possible consequence of this is that the company will waste money in replacing the tires. On the other hand, Type II error is committed when the airline company does not order tire replacement. A possible consequence of this Type II error is an accident that may happen because of no replacement of the tires. G. Making generalizations and abstractions about the lesson To generalize the lesson, the learners should be able to answer the following: 1. How do you differentiate null hypothesis and alternative hypothesis? 2. What is a statistical hypothesis? 3. How do you illustrate the two types of error in hypothesis testing? 175 H. Evaluating learning Choose the letter of the correct answer. 1. A Type II error is committed when a. we reject a null hypothesis that is true. b. we don't reject a null hypothesis that is true. c. we reject a null hypothesis that is false. d. we don't reject a null hypothesis that is false. 2. A Type I error is committed when a. we reject a null hypothesis that is true. b. we don't reject a null hypothesis that is true. c. we reject a null hypothesis that is false. d. we don't reject a null hypothesis that is false. 3. Selecting the significance level 𝛼 will determine a. the probability of a type I error b. the probability of a type II error c. power 4. Which of the following would be an appropriate null hypothesis? a. The mean of a population is equal to 50. b. The mean of a sample is equal to 50. c. The mean of a population is greater than 50. d. Only (a) and (c) are true. 5. Which of the following would be an appropriate alternative hypothesis? a. The mean of a population is equal to 50. b. The mean of a sample is equal to 50. c. The mean of a population is greater than 50. d. The mean of a sample is greater than 50 Answer: 1) d 2) a V.REMARKS VI. REFLECTION A. No. of learners who earned 80% on the formative assessment B. No. of learners who require additional activities for remediation C. Did the remedial lessons work? No. of 176 3) a 4) a 5) c learners who caught up with the lesson D. No. of learners who continue to require remediation E. Which of my teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/discover which I wish to share with other teachers? 177 School Teacher Time and Date I. OBJECTIVES A. Content Standards B. Performance Standards C. Learning Competencies/ Objectives II.CONTENT III. LEARNING RESOURCES A. References 1. Teacher’s Guide 2. Learner’s Materials Page 3. Textbook Pages IV.PROCEDURES A. Reviewing previous lesson or motivation Grade Level Learning Area Quarter 11 MATHEMATICS 3rd The learner demonstrates understanding of key concepts of tests of hypotheses on the population mean and population proportion The learner is able to perform appropriate tests of hypotheses involving the population mean and population proportion to make inferences in reallife problems in different disciplines. The learners • Illustrate level of significance and corresponding rejection region • Calculate the probabilities of committing a Type I and Type II error. M11/SP-Iva-2 Tests of Hypothesis Commission on Higher Education and Philippine Normal University (2016). Teaching Guide for Senior High School: Statistics and Probability. pp 375-378 Belecina, R. R.,Baccay E. S.,Mateo E. B. Statistics and Probability pp 226-235 Ask learners how a court trial proceeds based on their knowledge. Guide them by citing a popular case and letting them identify the steps to come up with a verdict for the case. For example, take the case of former President Marcos’ ill-gotten wealth case. List the steps that the learners identified. B. Establishing a purpose for the lesson They may mention the following: 1. State the accusation against the family of former President Marcos. 2. Choose the jury. Set or review the guidelines to be used in the decision-making process. 3. Present the evidences 4. Decide on the matter, based on the evidences. 5. State the verdict, based on the decision made. How can we relate the steps in conducting hypothesis testing on the steps in a court proceedings? How can we make a decision whether to reject or fail to reject (accept) the null 178 hypothesis? How can we determine the probability of making a correct decision in accepting or rejecting a true null hypothesis? C. Presenting examples/ instances of the new lesson The teacher will inform the students that the answers to those questions will be answered as the discussions go on. Emphasize that the steps in a court proceeding are similar if one has to conduct a test of hypothesis. Steps in Testing Hypothesis 1. Formulate the hypotheses to be tested. 2. State the decision rule that we will follow in making a decision on whether to reject or fail to reject (accept) the null hypothesis. D. Discussing new concepts and practicing new skills #1 Court proceedings 1. State the accusation or the statement of what will be evaluated as true or false 2. It is a guideline that the court uses to evaluate the quantity and quality of evidences to be presented. And based on this guideline, the court decides whether to reject or accept the hypothesis that the accused is not guilty. 3. Compute the value of the test statistic using a random sample of observations gathered or collected for the purpose of the test of hypothesis. 4. Use the decision rule to make a decision whether to reject or fail to reject (accept) the null hypothesis. 3. This is the time that the gathered evidences are presented. 5. State the conclusion. 5. This is the time when the court gives its verdict on the accused. In both scenarios, this last step is the most awaited part of the procedure. 4. The jury or the court will decide whether the accused is guilty or not based on the evidences presented. To be able to specify the decision rule in a hypothesis testing procedure, there is a need to specify the components of the rule. These components include the following: 1. Specify a level of significance, which is usually denoted as α in doing the test of hypothesis. A level of significance is 179 2. 3. the probability of rejecting a true null hypothesis or committing a Type I error in the test of hypothesis. Identify the test statistic to use in the decision rule. Part of the decision rule is the specification of the rejection region. The rejection region is that part of the distribution of the test statistic where we reject the null hypothesis. An example of a decision rule is stated as follows: “At a given α = 0.05, we reject Ho if the computed test statistic (denoted as tc) is greater than a tabular value of the t distribution with n-1 degrees of freedom. Otherwise, we fail to reject Ho.” E. Discussing new concepts and practicing new skills #2 The probability of committing an error is a conditional probability problem. It is the probability of making a decision based on the uncertainty of the true state of nature of the hypothesis being tested. Example: In testing the null hypothesis “The average daily number of text messages that a Grade 11 student sends is equal to 100” against an alternative hypothesis stated as “The average daily number of text messages that a Grade 11 student sends is greater than 100”. A random sample of 16 students were selected and interviewed. The daily number of text messages she sends is obtained. The null hypothesis is said to be rejected if the sample mean is at least 102, otherwise the null hypothesis will be accepted or we fail to reject Ho. It is assumed that the number of text messages that a Grade 11 student sends in a day follows a normal distribution with standard deviation equal to 5 text messages. Computing for the probability of committing Type I error, we have 𝛼 = 𝑃[𝑐𝑜𝑚𝑚𝑖𝑡𝑡𝑖𝑛𝑔 𝑎 𝑇𝑦𝑝𝑒 𝐼 𝑒𝑟𝑟𝑜𝑟] = 𝑃 [𝑅𝑒𝑗𝑒𝑐𝑡 𝐻𝑜I𝐻𝑜 𝑖𝑠 𝑇𝑟𝑢𝑒] 𝑋 − 100 ] = 𝑃[𝑍 ≥ 1.60] 5 √16 = 1 − 𝑃[𝑍 < 1.60] = 1 − 0.9452 = 0.0058 = 𝑃 [𝑋 ≥ 102 I 𝜇 = 100] = 𝑃 [ 180 Thus, probability of rejecting a true null hypothesis is 0.0058 or with 94.52% (1-0.0058 = 0.9452) confidence that we are making a correct decision in accepting a true null hypothesis. 𝛽 = 𝑃[𝑐𝑜𝑚𝑚𝑖𝑡𝑡𝑖𝑛𝑔 𝑎 𝑇𝑦𝑝𝑒 𝐼𝐼 𝑒𝑟𝑟𝑜𝑟] = 𝑃[𝐴𝑐𝑐𝑒𝑝𝑡 𝐻𝑜I𝐻𝑜 𝑖𝑠 𝐹𝑎𝑙𝑠𝑒] = 𝑃[𝐴𝑐𝑐𝑒𝑝𝑡 𝐻𝑜I𝐻𝑎 𝑖𝑠 𝑇𝑟𝑢𝑒] 𝑋 − 103 102 − 103 ] < 5 5 √16 √16 = 𝑃[𝑍 < −0.80] = 1 − 𝑃[𝑍 < 0.80] = 1 − 0.7881 = 0.2119 = 𝑃[𝑋 < 102 I 𝜇 = 103] = 𝑃 [ F. Developing mastery (Leads to Formative Assessment 3) Group Activity: (The class will be divided into 4 groups. Each group will be given the same problem. The activity is good only for 10-15 minutes. Consider the given problem. Answer what is being asked in the situation ) 1.The Graduate Record Exam (GRE) is a standardized test required to be admitted to many graduate schools in the United States. A high score in the GRE makes admission more likely. According to the Educational Testing Service, the mean score for takers of GRE who do not have training courses is 555 with a standard deviation of 139. Brain Philippines (BP) offers expensive GRE training courses, claiming their graduates score better than those who have not taken any training courses. To test the company’s claim, a statistician randomly selected 30 graduates of BP and asked their GRE scores. a. Formulate the appropriate null and alternative hypotheses. b. Identify situations when Type I and Type II errors are committed and state their possible consequences. c. Suppose the decision rule is “Reject Ho if the mean score of the sampled BP graduates is greater than 590; otherwise, fail to reject Ho.” Compute for the level of significance for this test. Also, find the risk of concluding that the BP graduates did not score better than 555 when in fact the mean score is 600. ANSWER: Ho: Graduates of BP courses did not score better than 555 while Ha: Graduates of BP courses did score better than 555. Type I error is committed when we declare that the company’s claim is true where in fact BP graduates do not perform better than 555 and a possible consequence is that the tuition fee paid for 181 the training is wasted. On the other hand, Type II is committed when we declare that the BP’s claim is false when in fact BP graduates do score better than 555 and a possible consequence is that opportunity to score better than 555 is lost The probability of Type I error is the same as the level of significance denoted by α. 𝛼 = 𝑃[𝑐𝑜𝑚𝑚𝑖𝑡𝑡𝑖𝑛𝑔 𝑎 𝑇𝑦𝑝𝑒 𝐼 𝑒𝑟𝑟𝑜𝑟] = 𝑃 [𝑅𝑒𝑗𝑒𝑐𝑡 𝐻𝑜I𝐻𝑜 𝑖𝑠 𝑇𝑟𝑢𝑒] 𝑋 − 555 590 − 555 ] ≥ 139 139 √30 √30 = 𝑃[𝑍 ≥ 1.38] = 1 − 𝑃[𝑍 < 1.38] = 1 − 0.9162 = 0.0838 = 𝑃 [𝑋 ≥ 590 I 𝜇 = 555] = 𝑃 [ On the other hand, the risk of concluding that the BP graduates did not score better than 555 when in fact their mean score is 600 is the probability of committing Type II and such risk or probability is computed as follows: 𝛽 = 𝑃[𝑐𝑜𝑚𝑚𝑖𝑡𝑡𝑖𝑛𝑔 𝑎 𝑇𝑦𝑝𝑒 𝐼𝐼 𝑒𝑟𝑟𝑜𝑟] = 𝑃[𝐴𝑐𝑐𝑒𝑝𝑡 𝐻𝑜I𝐻𝑜 𝑖𝑠 𝐹𝑎𝑙𝑠𝑒] = 𝑃[𝐴𝑐𝑐𝑒𝑝𝑡 𝐻𝑜I𝐻𝑎 𝑖𝑠 𝑇𝑟𝑢𝑒] 𝑋 − 600 590 − 600 ] < 139 139 √30 √30 = 𝑃[𝑍 < −0.80] = 1 − 𝑃[𝑍 < 0.80] = 1 − 0.7881 = 0.2119 = 𝑃[𝑋 < 590 I 𝜇 = 600] = 𝑃 [ G. Making generalizations and abstractions about the lesson H. Evaluating learning We can determine the probability of making a correct decision in accepting or rejecting a true null hypothesis by calculating the probabilities of committing a Type I and Type II error. It is the probability of making a decision based on the uncertainty of the true state of nature of the hypothesis being tested. We may use a numerical example and a formula to illustrate the computation of the probabilities of committing Type I and Type II errors. Consider the given problem and ask them to do what is being asked for. Consider a manufacturing process that is known to produce bulbs that have life lengths with a standard deviation of 75 days. A potential customer will purchase bulbs from the company that manufactures the bulbs if she is convinced that the average life of the bulbs is 1550 days. a. Formulate the appropriate null and alternative hypotheses. 182 b. Identify situations when Type I and Type II errors are committed and state their possible consequences. c. Suppose the decision rule is “Reject Ho if a random sample of 50 bulbs has a life less than 1532 days; otherwise, fail to reject Ho.” Compute for the level of significance for this test. Also, find the risk of concluding that the average is greater than 1550 days when in fact their mean score is 1500. ANSWER: a. Ho: null hypothesis, that the average life of bulbs is (at least) 1550 days against the alternative hypothesis, that the average is less than 1550 b. Type I error is committed when we declare that the average life is less than 1550 days where in fact the average life is 1550 days or more. On the other hand, Type II is committed when we declare that the average is at least 1550 days, when in fact, it is less than 1550 days. c. The probability of Type I error is the same as level of significance denoted by α. = 𝑃 [𝑐𝑜𝑚𝑚𝑖𝑡𝑡𝑖𝑛𝑔 𝑎 𝑇𝑦𝑝𝑒 𝐼 𝑒𝑟𝑟𝑜𝑟 ] = 𝑃 [𝑅𝑒𝑗𝑒𝑐𝑡 𝐻𝑜I𝐻𝑜 𝑖𝑠 𝑇𝑟𝑢𝑒] = 𝑃[𝑋 ≤ 1532 I 𝜇 = 1550] 𝑋 − 1550 1532 − 1550 ] ≤ 75 75 √50 √50 = 𝑃[𝑍 ≥ 1.38] = 1 − 𝑃[𝑍 ≤ 1 − 1.70] ≈ 0.04 = 𝑃[ V.REMARKS VI. REFLECTION A. No. of learners who earned 80% on the formative assessment B. No. of learners who require additional activities for remediation C. Did the remedial lessons work? No. of learners who caught up with the lesson D. No. of learners who continue to require remediation 183 E. Which of my teaching strategies worked well? Why did these work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized materials did I use/discover which I wish to share with other teachers? 184 School Teacher Time and Date OBJECTIVE S A. Content Standard Grade Level Learning Area Quarter 11 MATHEMATICS 3rd I. B. Performance Standard C. Learning Competencie s/ Objectives Write The LC code for each II. III. CONTENT The learner demonstrates understanding of key concepts of tests of hypotheses on the population mean. The learner is able to perform appropriate tests of hypotheses involving the population mean to make inferences in real-life problems in different disciplines. The learner identifies the parameter to be tested given a real-life problem. M11/12SP-IVa-3. Tests of Hypothesis LEARNING RESOURCE S A. References 1. Teacher’s Guide pages 2. Learner’s Material pages 3. Textbook pages 4. Additional Materials from Learning Resource (LR) portal B. Other Learning Resources IV. PROCEDURE A. Reviewing previous lesson or presenting the new lesson B. Establishing a purpose of the lesson Commission on Higher Education & Philippine Normal University (2016). Teaching Guide for Senior High School: Statistics and Probability. https://www.cliffsnotes.com/studyguides/statistics/sampling/populations Laptop, projector, powerpoint presentation Post the words PARAMETER and STATISTIC on the board. Ask the students to give the definition of the two words by writing them in a meta strips and post them in line with the given words. With the given problems below, identify the parameter to be tested. 1. The father of a senior high school student lists down the expenses he will incur when he sends his daughter to the university. At the university he wants his daughter to study, he hears that the average tuition fee is at least Php 20,000 per semester. 185 Ans.:The parameter to be tested is the average tuition fee or the true population mean of the tuition fee. 2. The principal of an elementary school believes that this year, there would be more students from the school who would pass the National Achievement Test (NAT), so that the proportion of students who passed the NAT is greater than the proportion obtained in previous year, which is 0.75. What will be the appropriate null and alternative hypotheses to test this belief? Ans.:The parameter to be tested is the proportion of students of the school who passed the NAT this year. C. Presenting examples/ instances of the new lesson D. Discussing new concepts and practicing new skills #1 A researcher wants to estimate the average height of women aged 20 years or older. From a simple random sample of 45 women, the researcher obtains a sample mean height of 63.9 inches. Which of the statements below is the parameter of the given situation? a. Average height of all women aged 20 years or older. b. Average height of 63.9 inches from the sample of 45 women. Discuss the answer of the activity, pointing out the difference between parameter and statistic. Present another problem. Let the students identify the parameter. A school administrator wants to estimate the mean score on the verbal portion of the SAT for students whose first language is not English. From a simple random sample of 20 students whose first language is not English, the administrator obtains a sample mean SAT verbal score of 458. Ans.:The parameter is the mean verbal SAT score for students whose first language is not English. QUIZ BEE E. Developing Mastery(Leads to Formative Assessment) Group the class into 5. Identify the parameter of each of the problems to be presented. 1. A nutritionist wants to estimate the mean amount of sodium consumed by children under the age of 10. From a random sample of 75 children under the age of 10, the nutritionist obtains a sample mean of 2993 milligrams of sodium consumed. ans.:The mean amount of sodium consumed by children under the age of ten. 2. Nexium is a drug that can be used to reduce the acid produced by the body and heal damage to the esophagus. A researcher wants to estimate the proportion of patients taking Nexium that are healed within 8 weeks. A random sample of 224 patients 186 suffering from acid reflux disease is obtained, and 213 of those patients were healed after 8 weeks. ans.:The proportion of patients healed by Nexium in 8 weeks. 3. A researcher wants to estimate the average farm size in Sorsogon. From a simple random sample of 40 farms, the researcher obtains a sample mean farm size of 731 acres. ans.:The average farm size in Sorsogon. 4. An energy official wants to estimate the average oil output per well in the Philippines. From a random sample of 50 wells throughout the Philippines, the official obtains a sample mean of 10.7 barrels per day. ans.:The average oil output per well in the Philippines. 5. An education official wants to estimate the proportion of adults aged 18 or older who had read at least one book during the previous year. A random sample of 1006 adults aged 18 or older is obtained, and 835 of those adults had read at least one book during the previous year. ans.:The proportion of adults 18 or older who read a book in the previous year. F. Making generalizations and abstraction about the lesson G. Finding practical applications of concepts and skills in daily living How to identify the parameter to be tested given a real life problem? How important is having knowledge on identifying the parameter to be tested of a real life problem? With the following problems,identify the parameter to be tested. H. Evaluating Learning 187 I. Additional activities for application or remediation V. REMARKS VI. REFLECTION A. No. of learners who earned 80% in the evaluation B. No. of learners who require additional activities for remediation who scored below 80% C. Did the remedial lesson work? No. of learners who have coped up with the lesson D. No. of learners who continue to require remediation E. Which of my teachings strategies worked well? Why did these work? F. What difficulties did I encounter which my principal/ supervisor can help me solve? G. What innovation or localized materials did I use/ discover which I wish to share with the other teachers? 188 SCHOOL GRADE LEVEL LEARNING AREA QUARTER TEACHER TIME& DATE I. OBJECTIVES A. Content Standard B. Performance Standard C. Learning Competencies/ Objectives Write The LC code for each II. 11 STATISTICS AND PROBABILITY CONTENT The learner demonstrates understanding of key concepts of tests of hypotheses on the population mean. The learner is able to perform appropriate tests of hypotheses involving the population mean to make inferences in real-life problems in different disciplines. The learner formulates the appropriate null and alternative hypotheses on a population mean. M11/12SP-IVb-1. Tests of Hypothesis III. LEARNING RESOURCES A. References 1. Teacher’s Guide pages Commission on Higher Education & Philippine Normal University (2016). Teaching Guide for Senior High School: Statistics and Probability. pp.374-375 2. Learner’s Material pages 3. Textbook pages 4. Additional Materials from Learning Resource (LR) portal https://stattrek.com/hypothesis-test/mean.aspx https://www.ck12.org/statistics/null-and-alternativehypotheses/lesson/Null-and-Alternative-Hypotheses-ADVPST/ cfcc.edu/faculty/cmoore/0801-HypothesisTests.pdf https:// m358k-ps-six-hypothesis-tests.pdf B. Other Learning Resources Manila paper, worksheet IV. pentel pen, powerpoint presentation, PROCEDURE A. Reviewing previous lesson or presenting the new lesson Arrange the steps of hypothesis testing procedures below: a. Make a decision whether to reject or fail to reject the null hypothesis. b. Using a simple random of observation, compute the value of the test statistic. c. Formulate the null and alternative hypotheses. d. State the conclusion. e. Identify the test statistic to use. With the given level of significance and the distribution of the test statistics, state the decision rule and specify the rejection region. 189 With the given problems below, formulate the null and alternative hypotheses. 1. The father of a senior high school student lists down the expenses he will incur when he sends his daughter to the university. At the university he wants his daughter to study, he hears that the average tuition fee is at least Php 20,000 per semester. He wants to do a test of hypothesis. B. Establishing a purpose of the lesson C. Presenting examples/ instances of the new lesson D. Discussing new concepts and practicing new skills #1 E. Developing Mastery(Leads to Formative Assessment) 2. The principal of an elementary school believes that this year, there would be more students from the school who would pass the National Achievement Test (NAT), so that the proportion of students who passed the NAT is greater than the proportion obtained in previous year, which is 0.75. What will be the appropriate null and alternative hypotheses to test this belief? Differentiate the two problems. Use the first problem to discuss the concept. Discuss the result of the activity, pointing out the following: A statistical hypothesis is a statement about a parameter and deals with evaluating the value of the parameter. The null and alternative hypotheses should be complementary and non-overlapping. Generally, the null hypothesis is a statement of equality or includes the equality condition as in the case of ‘at least’ ( greater than or equal) or ‘atmost’ (less than or equal). Present the situation below and ask the students to formulate the appropriate null and alternative hypotheses. “The average daily number of text messages that a Grade 11 student sends is equal to 100.” Group Activity The class will be divided into three groups. Each group will be given a worksheet. Rubric for Assessing the Activity 190 F. Making generalizations and abstraction about the lesson G. Finding practical applications of concepts and skills in daily living How to formulate null and alternative hypotheses? Cite some applications of the concepts learned in daily life. With the following problems, formulate the appropriate null and alternative hypotheses. H. Evaluating Learning I. Additional activities for application or remediation V. REMARKS 191 VI. REFLECTION A. No. of learners who earned 80% in the evaluation B. No. of learners who require additional activities for remediation who scored below 80% C. Did the remedial lesson work? No. of learners who have coped up with the lesson D. No. of learners who continue to require remediation E. Which of my teachings strategies worked well? Why did these work? F. What difficulties did I encounter which my principal/ supervisor can help me solve? G. What innovation or localized materials did I use/ discover which I wish to share with the other teachers? 192 School Teacher Time and Date Grade Level Learning Area Quarter 11 MATHEMATICS 3rd I.OBJECTIVES A. Content Standard The learner demonstrates understanding of key concepts of tests of hypotheses on the population mean and population proportion. B. Performance Standard The learner is able to perform appropriate tests of hypotheses involving the population mean and population proportion to make inferences in real-life problems in different disciplines. C. Learning Competency/Obje ctive: The learner identifies the appropriate form of the teststatistic when: (a) the population variance is assumed to be known (b) the population variance is assumed to be unknown; and (c) the Central Limit Theorem is to be used. II. CONTENT III.LEARNING RESOURCES A. References 1. Teacher’s guide pages 2. Learner’s material pages 3. Textbook pages 4. Additional materials from learning resource (LR) portal B. Other Learning Resource IV. PROCEDURE M11/12SP-IVb-2 Appropriate Form of the Test-Statistic 374-398 Statistics and Probability pp.246-265 A. Reviewing previous lesson or Reviewing the steps of hypothesis testing procedure: presenting the new 1. Formulate the null and alternative hypotheses. lesson 2. Identify the test statistic to use. With the given level of significance and the distribution of the test statistics, state the decision rule and specify the rejection region. 3. Using a simple random sample of observation, compute the value of the test statistic. 4. Make a decision whether to reject or fail to reject (accept) Ho. 5. State the conclusion. 193 B. Establishing a purpose for the lesson: How does test statistics play a very important role in the decision on Hypothesis Testing? The test statistic is a standardized expression of the point estimator of the parameter identified in the hypothesis. Also, the distribution of the test statistic is also needed to be specified. C. Presenting examples/instance TEST STATISTIC – a value used to determine the s of the new lesson probability needed in decision-making and a value determined by a computational formula that is compared with confidence coefficient (like 1.96 and 2.58) Problem #1 The father of a senior high school student lists down the expenses he will incur when he sends his daughter to the university. At the university where he wants his daughter to study, he hears that the average tuition fee is at least Php20,000 per semester. He wants to do a test of hypothesis. In this problem, the parameter of interest is the average tuition fee or the true population mean of the tuition fee. In symbol, this parameter is denoted as µ. As applied to the problem, the appropriate null and alternative hypotheses are: Ho: The average tuition fee in the targeted university is at least Php20,000. In symbols, Ho: µ ≥ Php20,000. Ha: The average tuition fee in the targeted university is less than Php20,000. In symbols, Ha: µ < Php20,000. In the problem, the parameter is the population mean. To identify the test statistics, which is part of the second step, certain assumptions have to be made. D. Discussing new concepts and practicing new skill #1 With the assumption of known population variance (σ2) and the variable of interest is measured at least in the interval scale and follows the normal distribution, the appropriate test statistic, denoted as Zc is computed as Zc = 𝑋−𝜇𝑜 𝜎/√𝑛 where X is the sample mean computed from a simple random sample of n observations; µ0 is the hypothesized value of the parameter; and σ is the population standard deviation. The test statistic follows the standard normal distribution which means the 194 tabular value in the Z-table will be used as critical or tabular value. With the assumption of unknown population variance (σ2) and the variable of interest is measured at least in the interval scale and follows the normal distribution, the appropriate test statistic, denoted as tC is computed as tc = 𝑋−𝜇𝑜 𝑠/√𝑛 where X and s, are the sample mean and sample standard deviation, respectively, computed from a simple random sample of n observations; and µ0 is the hypothesized value of the parameter. The test statistic follows the Student’s t-distribution with n-1 degrees of freedom which means the tabular value in the Student’s t-table will be used as critical or tabular value. E. Discussing concepts practicing skills #2 new and new Present the table to the class. 195 F. Developing GROUP ACTIVITY mastery (Leads to The class will be divided into 4 groups. Each group will Formative be given a corresponding problem for them to work on Assessment 3) and materials such as bond paper, pentel pen and manila paper. Direction: Identify the appropriate test statistic to be used on the following problem: GROUP 1: A researcher used a developed problem solving test to randomly select 50 Grade VI pupils. In this sample, X=80 and s=10. The mean µ and the standard deviation of the population used in the standardization of the test were 75 and 15, respectively. 196 ANSWER: Test Statistic Zc = 𝑋−𝜇𝑜 𝜎/√𝑛 GROUP 2: The owner of a factory that sells a particular bottled fruit juice claims that the average capacity of their product is 250 ml. To test the claim, a consumer group gets a sample of 100 such bottles, calculates the capacity of each bottle, and then finds the mean capacity to be 248 ml. The standard deviation s is 5 ml. ANSWER: Test Statistic tc = 𝑋−𝜇𝑜 𝑠/√𝑛 Group 3: The Graduate Record Exam (GRE) is a standardized test required to be admitted to many graduate schools in the United States. A high score in the GRE makes admission more likely. According to the Educational Testing Service, the mean score for takers of GRE who do not have training courses is 555 with a standard deviation of 139. Brain Philippines (BP) offers expensive GRE training courses, claiming their graduates score better than those who have not taken any training courses. To test the company’s claim, a statistician randomly selected 30 graduates of BP and asked their GRE scores. ANSWER: Test Statistic Zc = 𝑋−𝜇𝑜 𝜎/√𝑛 Group 4: A brand of powdered milk is advertised as having a net weight of 250 grams. A curious consumer obtained the net weight of 10 randomly selected cans. The values obtained are: 256, 248, 242, 245, 246, 248, 250, 255, 243 and 249 grams. Is there reason to believe that the average net weight of the powdered milk cans is less than 250 grams at 10% level of significance? Assume the net weight is normally distributed with unknown population variance. ANSWER: Test Statistic tc = G. Making generalizations and abstractions about the lesson H. Evaluating Learning 𝑋−𝜇𝑜 𝑠/√𝑛 The decision that we make depends on the computed test statistic. The formula for computing the test statistic depends on the sample size. Direction: Identify the appropriate test statistic to be used on the following problem: 1. The principal of an elementary school believes that this year, there would be more students from the school who would pass the National Achievement Test (NAT), so that the proportion of students who passed the NAT is greater than the proportion obtained in 197 previous year, which is 0.75. What will be the appropriate null and alternative hypotheses to test this belief? ANSWER: Test Statistic Zc = 𝑋−𝜇𝑜 𝜎/√𝑛 2. The minimum wage earners of the National Capital Region are believed to be receiving less than Php500 per day. The CEO of a large supermarket chain in the region is claiming to be paying its contractual higher than the minimum daily wage rate of Php500. To check on this claim, a labour union leader obtained a random sample of 144 contractual employees from this supermarket chain. The survey of their daily wage earnings resulted to an average wage of Php510 per day with standard deviation of Php100. The daily wage of the region is assumed to follow a distribution with an unknown population variance. Perform a test of hypothesis at 5% level of significance to help the labour union leader make an empiricalbased conclusion on the CEO’s claim. ANSWER: Test Statistic Zc = I. Additional activities for application or Remediation V. REMARKS VI. REFLECTION A. No. of learners who earned 80% on the formative assessment B. No. of learners who require additional activities for remediation. C. Did the remedial lessons work? No. of learners who have caught up with the lesson. D. No. of learners who continue to require remediation. E. Which of my teaching strategies worked well? Why did it work? F. What difficulties did I encounter which my 198 𝑋−𝜇𝑜 𝜎/√𝑛 principal or supervisor can help me solve? G. What innovation or localized material/s did I use/discover which I wish to share with other teachers? 199 School Teacher Time and Date Grade Level Learning Area Quarter 11 MATHEMATICS 3rd I.OBJECTIVES A. Content Standard The learner demonstrates understanding of key concepts of tests of hypotheses on the population mean and population proportion. B. Performance Standard The learner is able to perform appropriate tests of hypotheses involving the population mean and population proportion to make inferences in real-life problems in different disciplines. C. Learning Competency/Objecti ve: The learner identifies the appropriate rejection region for a given level of significance when: (a) the population variance is assumed to be known (b) the population variance is assumed to be unknown; and (c) the Central Limit Theorem is to be used. M11/12SP-IVc-1 II. CONTENT Appropriate Rejection Region III.LEARNING RESOURCES A. References 1. Teacher’s guide pages 2. Learner’s material pages 3. Textbook pages 4. Additional materials from learning resource (LR) portal B. Other Learning Resource IV. PROCEDURE 374-398 Statistics and Probability pp.246-265 A. Reviewing previous lesson or presenting Review the appropriate test statistics to be used the new lesson when: (a) the population variance is assumed to be known (b) the population variance is assumed to be unknown; and (c) the Central Limit Theorem is to be used B. Establishing a purpose for the lesson: Ask the learners what they will do in case the variable of interest cannot be assumed to follow a normal distribution. Is there a way to test the hypotheses? 200 The answer to this question is: Yes, there is a way to do it but they must be assured that the sample size is large enough to invoke the Central Limit Theorem they learned under the lesson on sampling distribution of the sample mean. Let us say that for the given problem, a random sample of size 36 is sufficient for us to invoke the theorem. C. Presenting examples/instances of the new lesson The father of a senior high school student lists down the expenses he will incur when he sends his daughter to the university. At the university where he wants his daughter to study, he hears that the average tuition fee is at least Php20,000 per semester. He wants to do a test of hypothesis. For the problem, the first is the appropriate decision rule. Suppose the level of significance (α) is set at 0.05, then the decision rule for the problem could be stated as ‘Reject Ho if Zc < -Z0.05 = -1.645. Otherwise, we fail to reject Ho.” Note that this test procedure is referred to as “one-tail Z-test for the population mean when the population variance is known’ and the rejection region is illustrated as follows: The father of a senior high school student lists down the expenses he will incur when he sends his daughter to the university where he wants her to study. He hypothesizes that the average tuition fee is at least Php20,000 per semester. He knows the variable of interest, which is the tuition fee, is measured at least in the interval scale or specifically in the ratio scale. He assumes that the variable of interest follows the normal distribution but both population mean and variance are unknown. The father asks, at random, 25 students of the university about their tuition fee per semester. He is able to get an average of Php20,050 with a standard deviation of Php500. 201 For the problem, the first is the appropriate decision rule. Suppose the level of significance (α) is set at 0.05, then the decision rule for the problem can be stated as “Reject Ho if the tc < -tα,24 = -2.064. Otherwise, we fail to reject Ho.” Note that this test procedure is referred to as “one-tail t-test for the population mean” and the rejection region is illustrated as follows: D. Discussing new concepts and practicing new skill #1 Present the table to the students while highlighting the appropriate rejection region. 202 203 E. Developing mastery (Leads to Formative GROUP ACTIVITY Assessment 3) The class will be divided into 3 groups. Each group will be given a corresponding problem for them to work on and materials such as bond paper, pentel pen and manila paper. Direction: Identify the appropriate rejection region to be used on the following problem: Group 1: The Graduate Record Exam (GRE) is a standardized test required to be admitted to many graduate schools in the United States. A high score in the GRE makes admission more likely. According to the Educational Testing Service, the mean score for takers of GRE who do not have training courses is 555 with a standard deviation of 139. Brain Philippines (BP) offers expensive GRE training courses, claiming their graduates score better than those who have not taken any training courses. To test the company’s claim, a statistician randomly selected 30 graduates of BP and asked their GRE scores. ANSWER: Group 2: The minimum wage earners of the National Capital Region are believed to be receiving less than Php500 per day. The CEO of a large supermarket chain in the region is claiming to be paying its contractual higher than the minimum daily wage rate of Php500. To check on this claim, a labour union leader obtained a random sample of 144 contractual employees from this supermarket chain. The survey of their daily wage earnings resulted to an average wage of Php510 per day with standard deviation of Php100. The daily wage of the region is assumed to follow a distribution with an unknown population variance. Perform a test of hypothesis at 5% level of 204 significance to help the labour union leader make an empiricalbased conclusion on the CEO’s claim. ANSWER: Group 3: A brand of powdered milk is advertised as having a net weight of 250 grams. A curious consumer obtained the net weight of 10 randomly selected cans. The values obtained are: 256, 248, 242, 245, 246, 248, 250, 255, 243 and 249 grams. Is there reason to believe that the average net weight of the powdered milk cans is less than 250 grams at 10% level of significance? Assume the net weight is normally distributed with unknown population variance. ANSWER: F. Making Ask a student to give generalization on how to generalizations and identify the appropriate rejection region given a abstractions about particular population variance. the lesson G. Evaluating Learning Direction: Identify the appropriate rejection region to be used on the following problem: 1. A researcher used a developed problem solving test to randomly select 50 Grade VI pupils. In this sample, X=80 and s=10. The mean µ and the standard deviation of the population used in the standardization of the test were 75 and 15, respectively. ANSWER: 205 H. Additional activities for application or Remediation V. REMARKS VI. REFLECTION A. No. of learners who earned 80% on the formative assessment B. No. of learners who require additional activities for remediation. C. Did the remedial lessons work? No. of learners who have caught up with the lesson. D. No. of learners who continue to require remediation. E. Which of my teaching strategies worked well? Why did it work? F. What difficulties did I encounter which my principal or supervisor can help me solve? G. What innovation or localized material/s did I use/discover which I wish to share with other teachers? 206 SCHOOL GRADE LEVEL LEARNING AREA QUARTER TEACHER TIME& DATE I. OBJECTIVES A. Content Standard B. Performance Standard C. Learning Competencies/ Objectives Write The LC code for each II. 11 STATISTICS AND PROBABILITY CONTENT The learner demonstrates understanding of key concepts of tests of hypotheses on the population mean The learner is able to perform appropriate tests of hypotheses involving the population mean to make inferences in real-life problems in different disciplines. M11/12SP-IVd-1. The learner computes for the test-statistics value (population mean). M11/12SP-IVd-2. Draws conclusion about the population mean based on the test-statistic value and the rejection region. Calculating Test-Statistic Value given that the population Variance is known III. LEARNING RESOURCES A. References 1. Teacher’s Guide pages Commission on Higher Education & Philippine Normal University (2016). Teaching Guide for Senior High School: Statistics and Probability. pp.372-384 2. Learner’s Material pages 3. Textbook pages 4. Additional Materials from Learning Resource (LR) portal B. Other Learning Resources IV. Hypothesis testing.WWW.ck12.org PROCEDURE A. Reviewing previous lesson or presenting the new lesson Complete the table below about the form of statistics to be used, the decision rule and the rejection region given the hypothesis and some assumptions about the distribution. Call some students to write their answers on the board. 207 Consider the situations below. B. Establishing a purpose of the lesson The father of a senior high school student lists down the expenses he will incur when he sends his daughter to a private college. At the school where he wants his daughter to study, he hears that the average tuition fee is at least Php20,000 per semester. He wants to know if this claim is true so he does a test of hypothesis. Suppose from a simple random sample of 16 students, a sample mean of Php19,750 was obtained. Further, the variable of interest, which is the tuition fee in the college, is said to be normally distributed with an assumed population variance equal to Php160,000. The students will be asked of the following questions. (Solicit students’ responses) 1. What hypotheses can be formulated based from the given situation? 2. What form of test-statistics is appropriate in the given problem? Emphasize that the lesson will focus on calculating the test-statistic value (about the population mean) and drawing conclusion about the population mean based on the test-statistic value and rejection region given that the population variance is known. C. Presenting examples/ instances of the new lesson D. Discussing new concepts and practicing new skills #1 Present to students the hypothesis testing procedures: a. Formulate the null and alternative hypotheses. b. Identify the test-statistic to use. With the given level of significance and the distribution of the test statistics, state the decision rule and specify the rejection region. c. Using a simple random sample of observation given in each problem, compute the value of the test statistic by applying the formula of test statistics identified in part b. d. Make a decision whether to reject or fail to reject Ho. e. State the conclusion. Using the situation about the tuition fee situation, calculate the test-statistic value following the hypothesis testing procedures. Students participation may be encouraged during the discussion. 208 c. Hypotheses: Ho: The average tuition fee in the targeted university is at least Php20,000. In symbols, Ho: μ ≥ Php20,000. Ha: The average tuition fee in the targeted university is less than Php20,000. In symbols, Ha: μ < Php20,000. d. Test-statistics to use: With the assumption of known population variance (σ2) and the variable of interest is measured at least in the interval scale and follows the normal distribution, the appropriate test statistic, denoted as ZC is computed as Where : is the sample mean computed from a simple random sample of n observations; μ0 is the hypothesized value of the parameter; and σ is the population standard deviation. Decision rule and Rejection Region: Suppose the level of significance (α) is set at 0.05, then the decision rule for the problem could be stated as Reject Ho if ZC < -Z0.05 = -1.645. Otherwise, we fail to reject Ho.” e. Compute for the value of the test statistic Given: = 19, 750 μ0 = 20, 000 σ2 = 160,000 σ = 400 Solution: -2.50 209 d. Making Decision Since the computed Z statistic value of -2.50 is less than the critical value of -1.645 at 0.05 level of significance, therefore we reject the null hypothesis. e. Conclusion With the rejection of the null hypothesis, the father can then say that the average tuition fee in the university where he wants his daughter to study is less than Php20,000. The class will be divided into 4 groups. Provide each group with the materials needed in accomplishing their tasks such as Hand-outs, permanent markers, calculator, manila paper. E. Developing Mastery(Leads to Formative Assessment) Each group will be assigned a problem to work with. For each problem, they will perform the following Test of Hypothesis procedures in order to calculate the test statistic value and be able to formulate a conclusion based from the result. (Use 0.05 level of significance to evaluate the hypothesis) a. Formulate the null and alternative hypotheses. b. Identify the test statistic to use. With the given level of significance and the distribution of the test statistics, state the decision rule and specify the rejection region. c. Using a simple random sample of observation given in each problem, compute the value of the test statistic by applying the formula of test statistics identified in part b. d. Make a decision e. State the conclusion. Tasks: Group 1 and 2. The school nurse thinks the average height of 7th graders has increased. The average height of a 7th grader five years ago was 145 cm with a standard deviation of 20 cm. She takes a random sample of 200 students and finds that the average height of her sample is 147 cm. Are 7th graders now taller than they were before? Group 3 and 4. Mang Ruben is trying out a planting technique that he hopes will increase the yield on his cacao trees. The average weight of yield on each tree is 80 kg with a standard deviation of 30 kg. This year, after trying his new planting technique, he takes a random sample 35 trees and finds the average weight of yield is to be 98 kg. He wonders whether or not this is a statistically significant increase. 210 Each group shall present their outputs in front. They will also compare their solution from the output of other groups. Check the solution of each group, and clarify some errors in their solutions. Summarize the lesson by emphasizing to students that with the assumption of known population variance (σ2) and the variable of interest is measured at least in the interval scale and follows the normal distribution, the appropriate test statistic, denoted as ZC is computed as F. Making generalizations and abstraction about the lesson Where : is the sample mean computed from a simple random sample of n observations; μ0 is the hypothesized value of the parameter; and σ is the population standard deviation. Emphasize to students that decisions are made about the hypothesis based on the result of the calculated statistical-value (ZC) at a given level of significance. This decision is used to formulate the conclusion. G. Finding practical applications of concepts and skills in daily living Quiz: Given the problem below, State the null hypothesis, calculate the statistical value and make a conclusion out of the resulted z-value. H. Evaluating Learning Consider a manufacturing process that is known to produce bulbs that have life lengths with a standard deviation of 75 days. A potential customer will purchase bulbs from the company that manufactures the bulbs if she is convinced that the average life of the bulbs is at least 1550 days. To test this, a random sample of 50 bulbs were tested and found to have an average life of 1532 days. Answer: Ho: The average life of the bulb is at least 1550 days. In symbols, μ ≥ 1550. Ha: The average life of the bulb is less than 1550 days. In symbols, μ < 1550. 211 Suppose the level of significance (α) is set at 0.05, then the decision rule for the problem could be stated as Reject Ho if ZC <-Z0.05 = -1.645. Otherwise, we fail to reject Ho.” -1.697 Since the computed Z statistic value of -1.697 is less than the critical value of -1.645 at 0.05 level of significance, therefore reject the null hypothesis. Because of the rejection of the null hypothesis, the potential costumer can conclude that the average life of the bulb is less than 1550 days. The consequences of this may lead the potential customer to not purchase the bulbs from that company. I. Additional activities for application or remediation V. REMARKS VI. REFLECTION A. No. of learners who earned 80% in the evaluation B. No. of learners who require additional activities for remediation who scored below 80% C. Did the remedial lesson work? No. of learners who have coped up with the lesson D. No. of learners who continue to require remediation E. Which of my teachings strategies worked well? Why did these work? F. What difficulties did I encounter which my principal/ supervisor can help me solve? 212 G. What innovation or localized materials did I use/ discover which I wish to share with the other teachers? 213 SCHOOL GRADE LEVEL LEARNING AREA QUARTER TEACHER TIME& DATE I. OBJECTIVES A. Content Standard B. Performance Standard C. Learning Competencies/ Objectives Write The LC code for each II. 11 STATISTICS AND PROBABILITY CONTENT The learner demonstrates understanding of key concepts of tests of hypotheses on the population mean The learner is able to perform appropriate tests of hypotheses involving the population mean to make inferences in real-life problems in different disciplines. M11/12SP-IVd-1. The learner computes for the teststatistics value (population mean). M11/12SP-IVd-2. Draws conclusion about the population mean based on the test-statistic value and the rejection region. Calculating Test-Statistic Value given that the population Variance is UNKNOWN III. LEARNING RESOURCES A. References 1. Teacher’s Guide pages 2. Learner’s Material pages 3. Textbook pages 4. Additional Materials from Learning Resource (LR) portal B. Other Learning Resources IV. PROCEDURE A. Reviewing previous lesson or presenting the new lesson Commission on Higher Education & Philippine Normal University (2016). Teaching Guide for Senior High School: Statistics and Probability. pp.372-384 https://courses.edx.org/c4x/UTAustinX/UT.7.01x/asset/Chapter_12.pdf Check-point: Ask the students to identify from the following the terms which they are familiar with. Ask them to define those terms based from their understanding. f. Normal Distribution g. T-Distribution h. Critical value i. Rejection region j. Degrees of Freedom 214 Consider the situations below. The high school MAPEH Teacher asked if the athletes in their school are doing as well academically as the other student athletes. We know from a previous study that the average Final Rating of the student athletes is 87. After an initiative to help improve the academic ratings of student athletes, the MAPEH teacher randomly samples 20 athletes and finds that the average Final Ratings of the sample is 88.8. with a sample standard deviation of 15. Is there a significant improvement? Use a 0.05 significance level. B. Establishing a purpose of the lesson The students will be asked of the following questions. (Solicit students’ responses) 3. What hypotheses can be formulated based from the given situation? 4. What form of test-statistics is appropriate in the given problem? Emphasize that the lesson will focus on calculating the test-statistic value (about the population mean) and drawing conclusion about the population mean based on the test-statistic value and rejection region given that the population variance is unknown. C. Presenting examples/ instances of the new lesson Present to students the hypothesis testing procedures: f. Formulate the null and alternative hypotheses. g. Identify the test-statistic to use. With the given level of significance and the distribution of the test statistics, state the decision rule and specify the rejection region. h. Using a simple random sample of observation given in each problem, compute the value of the test statistic by applying the formula of test statistics identified in part b. i. Make a decision whether to reject or fail to reject Ho. j. State the conclusion. D. Discussing new concepts and practicing new skills #1 Using the situation about the tuition fee situation, calculate the test-statistic value following the hypothesis testing procedures. Students participation may be encouraged during the discussion. a. Hypotheses: Ho: The average Final rating of the student athletes is equal to 87. In symbols, Ho: μ = 87. 215 Ha: The average Final rating of the student athletes is not equal to 87. In symbols, Ho: μ ≠ 87. b. Test-statistics to use: With the assumption of unknown population variance (σ2), the appropriate test statistic, is the T-test denoted as TC is computed as TC Where : TC is the test statistic and has n-1 degrees of freedom is the sample mean computed from a simple random sample of n observations; μ0 is the hypothesized value of the parameter; and S is the sample standard deviation. Decision rule and Rejection Region: Suppose the level of significance (α) is set at 0.05, then the decision rule for the problem is: Reject Ho if |tC|> ± 2.093 0.05/2, 19. Otherwise, we fail to reject Ho. c. Compute for the value of the test statistic Given: = 88.8 μ0 = 87 s = 15 n = 20 Solution: Tc Tc = Tc = 0.537 d. Making Decision Since the computed T statistic value of 0.537 is less than the critical value of ± 2.093 at 0.05 level of significance, therefore we fail to reject the null hypothesis. e. Conclusion Therefore, the average final rating of the sample of student athletes is not significantly different from the average final rating of student athletes. Therefore, we can conclude that the difference between the sample mean 216 and the hypothesized value is not sufficient to attribute it to anything other than sampling error. Thus, the MAPEH teacher can conclude that the mean academic performance of the athletes does not differ from the mean performance of other athletes. The class will be divided into 4 groups. Provide each group with the materials needed in accomplishing their tasks such as Hand-outs, permanent markers, calculator, manila paper. E. Developing Mastery(Leads to Formative Assessment) Each group will be assigned a problem to work with. For each problem, they will perform the following Test of Hypothesis procedures in order to calculate the test statistic value and be able to formulate a conclusion based from the result. (Use 0.05 level of significance to evaluate the hypothesis) f. Formulate the null and alternative hypotheses. g. Identify the test statistic to use. With the given level of significance and the distribution of the test statistics, state the decision rule and specify the rejection region. h. Using a simple random sample of observation given in each problem, compute the value of the test statistic by applying the formula of test statistics identified in part b. i. Make a decision j. State the conclusion. Tasks: Group 1 and 2. “Duracell manufactures batteries that the CEO claims will last an average of 300 hours under normal use. A researcher randomly selected 20 batteries from the production line and tested these batteries. The tested batteries had a mean life span of 270 hours with a standard deviation of 50 hours. Do we have enough evidence to suggest that the claim of an average lifetime of 300 hours is false?” Group 3 and 4. “The father of a senior high school student lists down the expenses he will incur when he sends his daughter to the university where he wants her to study. He hypothesizes that the average tuition fee is at least Php20,000 per semester. He knows the variable of interest, which is the tuition fee, is measured at least in the interval scale or specifically in the ratio scale. He assumes that the variable of interest follows the normal 217 distribution but both population mean and variance are unknown. The father asks, at random, 25 students of the university about their tuition fee per semester. He is able to get an average of Php20,050 with a standard deviation of Php500.” Each group shall present their outputs in front. They will also compare their solution from the output of other groups. Check the solution of each group, and clarify some errors in their solutions. Summarize the lesson by emphasizing to students that with the assumption of unknown population variance (σ2) and the variable of interest is measured at least in the interval scale and follows the normal distribution, the appropriate test statistic, denoted as TC is computed as F. Making generalizations and abstraction about the lesson Tc Where : TC is the test statistic and has n-1 degrees of freedom is the sample mean computed from a simple random sample of n observations; μ0 is the hypothesized value of the parameter; and S is the sample standard deviation. Emphasize to students that decisions are made about the hypothesis based on the result of the calculated statistical-value (TC) at a given level of significance. This decision is used to formulate the conclusion. G. Finding practical applications of concepts and skills in daily living Quiz: Given the problem below, State the null hypothesis, calculate the statistical value and make a conclusion out of the resulted T-value. H. Evaluating Learning A brand of powdered milk is advertised as having a net weight of 250 grams. A curious consumer obtained the net weight of 10 randomly selected cans. The values obtained are: 256, 248, 242, 245, 246, 248, 250, 255, 243 and 249 grams. Is there reason to believe that the average net weight of the powdered milk cans is less than 250 grams at 10% level of significance? Assume the net weight is 218 normally distributed with unknown population variance. Answer: Ho: The average net weight of the powdered milk cans is equal to 250 grams. In symbols, μ = 250 Ha: The average net weight of the powdered milk cans is equal to 250 grams. In symbols, μ< 250 With 10% level of significance, the decision rule is “Reject the null hypothesis (Ho) if the t C < -t0.10,9 = -2.998.” With the computed test statistic equal to -1.23, the null hypothesis is not rejected. We can then say that the advertised average net weight of the powdered milk is indeed true or μ = 250 grams. I. V. Additional activities for application or remediation REMARKS VI. REFLECTION A. No. of learners who earned 80% in the evaluation B. No. of learners who require additional activities for remediation who scored below 80% C. Did the remedial lesson work? No. of learners who have coped up with the lesson D. No. of learners who continue to require remediation E. Which of my teachings strategies worked well? Why did these work? 219 F. What difficulties did I encounter which my principal/ supervisor can help me solve? G. What innovation or localized materials did I use/ discover which I wish to share with the other teachers? 220 Solution to Problems A. Group Task Duracell manufactures batteries that the CEO claims will last an average of 300 hours under normal use. A researcher randomly selected 20 batteries from the production line and tested these batteries. The tested batteries had a mean life span of 270 hours with a standard deviation of 50 hours. Do we have enough evidence to suggest that the claim of an average lifetime of 300 hours is false? a. Formulate the null and alternative hypotheses. Ho: μ = 300. Ha: μ ≠ 300. b. Identify the test statistic to use. With the given level of significance and the distribution of the test statistics, state the decision rule and specify the rejection region. With the assumption of unknown population variance (σ2), the appropriate test statistic, is the T-test denoted as TC is computed as TC Suppose the level of significance (α) is set at 0.05, then the decision rule for the problem is: Reject Ho if |tC|> ± 2.093 0.05/2, 19. Otherwise, we fail to reject Ho. c. Using a simple random sample of observation given in each problem, compute the value of the test statistic by applying the formula of test statistics identified in part b. TC = -2.68 d. Make a decision Since our calculated t-test value is outside of our t-critical value –it lies in the critical region – we reject the Null Hypothesis. e. State the conclusion. The average battery life of the sample is significantly different from the average battery life claim by the CEO. 2. “The father of a senior high school student lists down the expenses he will incur when he sends his daughter to the university where he wants her to study. He hypothesizes that the average tuition fee is at least Php20,000 per semester. He 221 knows the variable of interest, which is the tuition fee, is measured at least in the interval scale or specifically in the ratio scale. He assumes that the variable of interest follows the normal distribution but both population mean and variance are unknown. The father asks, at random, 25 students of the university about their tuition fee per semester. He is able to get an average of Php20,050 with a standard deviation of Php500.” f. Formulate the null and alternative hypotheses. Ho: μ ≥ 20, 000. Ha: μ < 20, 000. g. Identify the test statistic to use. With the given level of significance and the distribution of the test statistics, state the decision rule and specify the rejection region. With the assumption of unknown population variance (σ2), the appropriate test statistic, is the T-test denoted as TC is computed as TC Suppose the level of significance (α) is set at 0.05, then the decision rule for the problem is: Reject Ho if tC < -1.7110.05, 24. Otherwise, we fail to reject Ho. h. Using a simple random sample of observation given in each problem, compute the value of the test statistic by applying the formula of test statistics identified in part b. TC = 0.5 i. Make a decision Since our calculated t-test value is outside of our t-critical value, we fail to reject the Null Hypothesis. j. State the conclusion. With the acceptance of the null hypothesis, the father can say that the average tuition fee at the university where he wanted his daughter to study is at least Php20,000. 222 Solution to Problems A. Group Task 1. The school nurse thinks the average height of 7th graders have increased. The average height of a 7th grader five years ago was 145 cm with a standard deviation of 20 cm. She takes a random sample of 200 students and finds that the average height of her sample is 147 cm. Are 7th graders now taller than they were before? k. Formulate the null and alternative hypotheses. Ho: The average height of 7th graders is less than or equal to 145 cm. In symbols, μ ≤ 145. Ha: The average height of 7th graders is more than 145 cm. In symbols, μ > 145. l. Identify the test statistic to use. With the given level of significance and the distribution of the test statistics, state the decision rule and specify the rejection region. With the assumption of known population variance (σ 2) and the variable of interest is measured at least in the interval scale and follows the normal distribution, the appropriate test statistic, denoted as ZC is computed as Suppose the level of significance (α) is set at 0.05, then the decision rule for the problem could be stated as Reject Ho if ZC > Z0.05 = 1.645. Otherwise, we fail to reject Ho.” m. Using a simple random sample of observation given in each problem, compute the value of the test statistic by applying the formula of test statistics identified in part b. Given: μ0 σ n = 147 = 145 = 20 = 200 Solution: 1.414 n. Make a decision Since the computed Z statistic value of 1.414 is less than the critical value of 1.645 at 0.05 level of significance, therefore we fail to reject the null hypothesis. o. State the conclusion. Because of not rejecting the null hypothesis, the school nurse can conclude that the average height of the 7th graders did not increase. 2. Mang Ruben is trying out a planting technique that he hopes will increase the yield on his cacao trees. The average weight of yield on each tree is 80 kg with a standard deviation of 30 kg. This year, after trying his new planting technique, he takes a random sample of 35 trees and finds the average weight of yield is to be 98 kg. He wonders whether or not this is a statistically significant increase. a. Formulate the null and alternative hypotheses. Ho: The average weight of yield on each tree is less than or equal to 145 kg. In symbols, μ ≤ 80. Ha: The average weight of yield on each tree is more than 80 kg. In symbols, μ > 80. 223 b. Identify the test statistic to use. With the given level of significance and the distribution of the test statistics, state the decision rule and specify the rejection region. With the assumption of known population variance (σ 2) and the variable of interest is measured at least in the interval scale and follows the normal distribution, the appropriate test statistic, denoted as ZC is computed as Suppose the level of significance (α) is set at 0.05, then the decision rule for the problem could be stated as Reject Ho if ZC > Z0.05 = 1.645. Otherwise, we fail to reject Ho.” c. Using a simple random sample of observation given in each problem, compute the value of the test statistic by applying the formula of test statistics identified in part b. Given: μ0 σ n = 98 = 80 = 30 = 35 Solution: 3.550 d. Make a decision Since the computed Z statistic value of 3.550 is more than the critical value of 1.645 at 0.05 level of significance, therefore reject the null hypothesis. e. State the conclusion. Because of rejecting the null hypothesis, Mang Ruben can conclude that with the application of the new farming technique brought a significant increase on the yield of his cacao trees. Meaning, this new farming technique is effective to increase the yield of cacao trees. 224 School Teacher Time and Date I. Grade Level Learning Area Quarter 11 MATHEMATICS 3rd OBJECTIVES A. Content Standard B. Performance Standard C. Learning Competencies/ Objectives Write The LC code for each II. CONTENT III. LEARNING RESOURCES A. References 1. Teacher’s Guide pages 2. Learner’s Material pages 3. Textbook pages 4. Additional Materials from Learning Resource (LR) portal B. Other Learning Resources IV. PROCEDURE A. Reviewing previous lesson or presenting the new lesson The learners demonstrate understanding of key concepts of tests of hypotheses on the population mean and population proportion. The learner is able to perform appropriate tests of hypotheses involving the population mean and population proportion to make inferences in reallife problems in different discipline. The learner solves problems involving tests of hypothesis on the population mean M11/12SP-IVe-1 TEST ON POPULATION MEAN Statistics and Probability, pages 374-384 Start the lesson by reviewing the steps of hypothesis testing procedure: 1. Formulate the null and alternative hypotheses 2. Identify the test statistic to use. With the given level of significance and the distribution of the test statistics, state the decision rule and specify the rejection region. 3. Using a simple random sample of observation, compute the value of the test statistic. 4. Make decision whether to reject or fail to reject the H0. 5. State the conclusion. 225 B. Establishing a purpose of the lesson C. Presenting examples/ instances of the new lesson D. Discussing new concepts and practicing new skills #1 Post the problem on the board/ project it using the projector. The father of a senior high school student lists down the expenses he will incur when he sends his daughter to the university where he wants her to study. He hypothesized that the average tuition/ miscellaneous fee is at least Php20, 000 per semester. He knows the variable of interest which is the tuition/ miscellaneous fee, is measured at least in the interval scale or especially in the ratio scale. He assumes that the variable of interest follows the normal distribution but booth population mean and variance are unknown. The father asks, at random, 25 students of the university about their tuition/ miscellaneous fee per semester. He is able to get an average of Php20, 050 with standard deviation of Php500. Let the student analyze the problem. The class will be group with 5 members. Each member will have a piece of colored paper to be used in the activity. Each students will follow the path, wherein they cannot pass until their answer is correct ( the teacher/ selected students will checked). The first group who finishes the task will be having an additional 5 points and the rest will have 4, 3, 2, and 1 depending on the time they finish the task. Each group will discuss first the situation and plan some strategies to perform the activity in the fastest way. E. Discussing new concepts and practicing new skills #2 F. Developing Mastery(Leads to Formative Assessment) STEP 1 Let the students identify the null hypothesis (𝐻0 ) and the alternative hypothesis (𝐻𝑎 ). H0: the average tuition fee in the targeted university is at least Php20, 000. : 𝐻0 : 𝜇 ≥ 20, 000 𝑝𝑒𝑠𝑜𝑠 Ha: the average tuition fee in the targeted university is less than Php20, 000. :𝐻𝑎 : 𝜇 < 20, 000 𝑝𝑒𝑠𝑜𝑠 226 STEP 2 With the assumption of unknown population variance (𝜎 2 ) and the variable of interest is measured at least in the interval scale and follows the normal distribution. The appropriate test statistic, denoted as 𝑡𝑐 𝑥̅ −𝜇 is computed as 𝑡𝑐 = 𝑠 0 , where 𝑥̅ and 𝑠 √𝑛 are the sample mean and standard deviation, respectively, computed from a simple random sample of 𝑛 observation; and 𝜇0 is the hypothesized value of the parameter. The decision rule cam be one of the following possibilities: 1. Reject 𝐻0 if 𝑡𝑐 < −𝑡𝑎 , 𝑛 − 1 . Otherwise, we fail to reject 𝐻0 2. Reject 𝐻0 if 𝑡𝑐 < 𝑡𝑎 , 𝑛 − 1. Otherwise, we fail to reject 𝐻0 3. Reject 𝐻0 if |𝑡𝑐 | < 𝑡𝑎/2 , 𝑛 − 1. Otherwise, we fail to reject 𝐻0 Suppose the level of the significance (𝛼) is set at 0.05, then the decision rule of the problem can be stated as “Reject 𝐻0 if the𝑡𝑐 < −𝑡𝛼,24 = −2.064”. Otherwise, we fail to reject𝐻0 . rejected region G. Making generalizations and abstraction about the lesson −𝑡𝛼,𝑛−1 = −2.064 STEP 3 𝑥̅ − 𝜇0 20, 050 − 20, 000 𝑡𝑐 = = = 0.50 𝑠 500 √𝑛 √25 STEP 4 Fail to reject the null hypothesis STEP 5 We can conclude that the father can say that the average tuition fee at the university where he wanted his daughter to study is at least Php20, 000 The students will summarize the lesson today by identifying the null hypothesis, alternative hypothesis, assumptions, appropriate statistic and the decision rule and rejected region. 227 How do you solve problems involving hypothesis testing on the population mean? H. Finding practical applications of concepts and skills in daily living I. Evaluating Learning Worksheet and answer sheet will be distributed by the teacher and the students will be paired for this activity. A researcher used s developed problem solving test to randomly selected grade 11 students. In this sample, 𝑥̅ = 80 and 𝑠 = 10. The 𝜇 and the standard deviation of the population used in the standardization of the test were 75 and 15 respectively. Use the 95% confidence level to answer the following questions: Does the sample mean differ significantly from the population mean? J. Additional activities for application or remediation V. REMARKS VI. REFLECTION A. No. of learners who earned 80% in the evaluation B. No. of learners who require additional activities for remediation who scored below 80% 228 C. Did the remedial lesson work? No. of learners who have coped up with the lesson D. No. of learners who continue to require remediation E. Which of my teachings strategies worked well? Why did these work? F. What difficulties did I encounter which my principal/ supervisor can help me solve? G. What innovation or localized materials did I use/ discover which I wish to share with the other teachers? 229 School Teacher Time and Date I. Grade Level Learning Area Quarter 11 MATHEMATICS 3rd OBJECTIVES A. Content Standard B. Performance Standard C. Learning Competencies/ Objectives Write The LC code for each II. CONTENT III. LEARNING RESOURCES A. References 1. Teacher’s Guide pages 2. Learner’s Material pages 3. Textbook pages The learners demonstrate understanding of key concepts of tests of hypotheses on the population mean and population proportion. The learner is able to perform appropriate tests of hypotheses involving the population mean and population proportion to make inferences in reallife problems in different discipline. The learner formulates the appropriate null and alternative hypotheses on a population proportion M11/12SP-IVe-2 TEST ON POPULATION PROPORTION Statistics and Probability, pages 385-389 Statistics and Probability for Senior High School, Jimczyville Publications, pages 169-176 4. Additional Materials from Learning Resource (LR) portal B. Other Learning Resources IV. Teacher’s Guide Laptop activity Sheets Power Point presentation Projector Strips of Colored Paper PROCEDURE A. Reviewing previous lesson or presenting the new lesson Activity #1 THERE’S MY PATH! (attached) Students will look for the right path in a maze. Every word that they pass through will be put in a strip of paper and post it in front. Answer: Formulate the null and alternative hypothesis on the population proportion. Review of Terms: Types of HypothesisPopulation Proportion 230 B. Establishing a purpose of the lesson Post the problem on the board/ project it using the projector. The principal of Rawis National High School believes that this year there would be more students from the school who pass the National Achievement Test (NAT), so that the proportion of the students who passed the NAT is greater than the proportion obtained in previous year, which is 0.75. Questions: 1. What can you say about the given situation? 2. How it is differ from problems in previous lesson about hypothesis testing on population mean? 3. What would be the appropriate null and alternative hypothesis to test this belief?(students answer will be noted) The teacher will introduce the concept of population proportion. After discussing the concept of population proportion, present the null and alternative hypothesis of the given problem. C. Presenting examples/ instances of the new lesson 𝐻0 : The proportion of students of the school who pass the NAT this year is equal to 0.75. In symbol, 𝑃 = 0.75 𝐻𝑎 : The proportion of students of the school who pass the NAT this year is greater than 0.75. In symbol, 𝑃 > 0.75 The teacher will post the situation to the students. And the teacher will guide the students in finding null hypothesis and alternative hypothesis A random sample of 750 students is selected, of whom 92 are left- handed. Use this sample data to test the claim that 10% of the students are left- handed. Discussing new concepts and practicing new skills #1 𝐻0 : 𝑃 = 0.10 𝐻𝑎 : 𝑃 ≠ 0.10 An independent research group is interested to show that the percentage of babies delivered through Caesarian Section is decreasing. For the past years, 20% of the babies were delivered through Caesarian Section. The research group randomly inspects the medical records of 144 births and finds that 25 of the births were by Caesarian Section. 231 𝐻0 : The proportion of births that were delivered by Caesarian Section is not decreasing, that is, it is still at least equal to 0.20. In symbol, 𝑃 ≥ 0.20 𝐻𝑎 : the proportion of births that were delivered by Caesarian Section is decreasing, that is, it is less than 0.20. in symbol, 𝑃 < 0.20 D. Discussing new concepts and practicing new skills #2 The class will be group into 4. The teacher will post problems on the board. In a few minutes, let the students talk about themselves the null and alternative hypothesis of the given situation. And after a while, the teacher will call one student coming from a group to answer the null hypothesis and alternative hypothesis. E. Developing Mastery(Leads to Formative Assessment) A machine is known to produce 20% defective products, and is therefore sent for repair. After the machine is repaired, 400 products produced by the machine are chosen at random and 64 of them found to be defective. Do the data provide enough evidence that the proportion of defective products produced by the machine has been reduced as a result of the repair? 𝐻0 :. 𝑃 = 0.20 (no change; the repair did not help) 𝐻0 :. 𝑃 < 0.20 (the repair was effective at reducing the proportion of defective parts) Polls on certain topics are conducted routinely in order to monitor changes in the public’s opinions over time. One such topic is the death penalty. In 2003 a pool estimated that 64% of adults support the death penalty for a person convicted to murders. Do the results of this pool provide evidence that the proportion of adults who support the death penalty for convicted murderers change between 2003 and the later pool? 232 F. Making generalizations and abstraction about the lesson G. Finding practical applications of concepts and skills in daily living H. Evaluating Learning I. Additional activities for application or remediation V. REMARKS VI. REFLECTION How do we formulate the null hypothesis and alternative hypothesis of the population proportion of every problem? Students will cite at least three situations when the test of proportion is applicable. Worksheet and answer sheet will be distributed by the teacher and the students will be paired for this activity. Mr. Alba asserts that fewer than 5% of the bulbs that he sells are defective. Suppose 300 bulbs are randomly selected, each is tested and 10 defective bulbs are found. What is appropriate null and alternative hypothesis can be formulated? A. No. of learners who earned 80% in the evaluation B. No. of learners who require additional activities for remediation who scored below 80% C. Did the remedial lesson work? No. of learners who have coped up with the lesson D. No. of learners who continue to require remediation E. Which of my teachings strategies worked well? Why did these work? F. What difficulties did I encounter which my 233 principal/ supervisor can help me solve? G. What innovation or localized materials did I use/ discover which I wish to share with the other teachers? 234 235 School Teacher Time and Date I. OBJECTIVES A. Content Standard B. Performance Standards C. Learning Competency Grade Level Learning Area Quarter 11 MATHEMATICS 3rd The learner demonstrates understanding of key concepts of test of hypothesis on the population mean and population proportion. The learner is able to perform appropriate tests of hypotheses involving the population mean and the population proportion to make inferences in real – life problems in different disciplines. M11/12 SP – IVe-4 Identifies the appropriate rejection region for a given level of significance when the central limit theorem is to be used. Performance Indicators: 1. Illustrate graphically the rejection region and acceptance region for a given level of significance or confidence level. 2. Given a 2 – value with a level of significance/confidence level, indicate if it is in the rejection region or acceptance region. Testing Hypothesis Involving Population Proportion II. CONTENT III. LEARNING RESOURCES A. References 1. Teacher’s Guide 2. Learners’ Materials 3. Reference Books 4. Additional Materials for Learning B. Other Learning Statistics and Probability by Belecina, et.al Resources IV. Instructional Procedure 1. Activity Activity 1 (Teacher’s Activity) Review by showing the following tables: Table 1. Four Possible Outcome in Decision Making Decision About H0 Do not reject H0 Reject (or accept H0) Type I Correct H0 is true error Decision Reality Correct Type II H0 is falsr Decision error Table 2. Types of Errors 236 Error Type Proba Correc Type Proba in bility t bility decisi Decisi on on Reject I α Accept A 1–α a true a true H0 H0 Accept II β Reject B 1–β a false a false H0 H0 Teacher’s Input (Exposition) In hypothesis testing, decisions are made. Errors are likely to be committed. The best that can be done is to control the probability with which an error occurs. The types of errors and some details are shown in tables 1 and 2. The most frequently used probability values for α and β are 0.05 (5%) and 0.01 (1%). Below are the graphical representations of a two – tailed (non – directional) test and one – tailed (directional) tests. The shaded parts are the rejection regions while the unshaded are the acceptance regions. Two – tailed (non – directional): both Critical Value 𝛼 2 Critical the probability is found on Value tails of𝛼the distribution. 2 1α M One – tailed, left tail: the probability is found at the left tail of the distribution. One – tailed, right tail: the probability is found at the right tail of the distribution. Activity 2 (Students’ Activity) (Let the class work in small groups of three members and give/distribute metacards where either one of these two problems are written. Let them work for 5 minutes. 1. Identify the given data and answer the questions that follow. 237 2. Analysis For a 95% confidence level or level of significance, what is the value of α? What are the critical values for a one – tailed test? What are the critical values for a two – tailed test? Show the data and the critical values (in a normal curve) graphically. 2. Identify the given data and answer the questions that follow. For a 99% confidence level or level of significance, what is the value of α? What are the critical values for a one – tailed test? What are the critical values for a two – tailed test? Show the data and the critical values graphically. (Call on volunteers to present groups’ outputs and answers) (Teacher processes the outputs and answers given or shown by the volunteers. Teacher may add inputs and correct misconception, if there are. Teaching Notes: For a 95% confidence level or level of significance, two 0.95 – tailed = 0.4750, in the normal curve, this area 2 corresponds to Z = 1.96. Hence, critical values for 95% confidence level or level of significance are ± 1.96. Graphical representation is shown below. For a 95% confidence interval or level of significance, one – tailed, 5% from the extreme left or right is bounded by the critical value. To compute for it, 0.50 – 0.05 = 0.4500, this area corresponds to a z – value which is 1.65. Hence, the critical values are ± 1.65. Below is the graphical representation. 238 Right – tailed Left – tailed For a 99% confidence level or level of significance, two .99 – tailed, = 0.4950 and this area corresponds to two 2 2 z – values, 257 and 2.58. in this case, the larger the value is considered. Two – tailed For a 99% confidence level or level of significance, one – tailed, 1% from the extreme left or right is bounded by the critical value. To compute, 0.50 – 0.01 = 0.4950 and this area corresponds to a z – value which is 2.33. hence, the critical values are ± 2.33. 239 Left – tailed Right – tailed 3. Abstraction (Teacher leads the class to formulate generalization ) Students’ Activity: Based from the previous activity and discussions, gather important information and fill the table with missing data. DIRECTION: Fill the table below with appropriate/correct data. Confidence Level Two – Tailed One – Tailed -Zα/2 = -z = 95% ( 1 – α) Zα/2 = z= -Zα/2 = -z = 99% (1 – α) Zα/2 = z= Provision for practice: Given: Z = 2, 95% confidence level/level of significance, two tailed. Do the following: Draw the normal curve Locate the z- value Indicate if the z – value is in the rejection or acceptance region. Expected answer: z = 2, 95% confidence level, two – tailed (non – directional) critical values: ± 1.96 240 4. Application Home Task (For Reflection) (Pen – and – paper activity) For each of the given set of data, do the following: 1. Draw the normal curve. 2. Locate the z – value. 3. Indicate if the z – value is in the rejection or acceptance region. a. z = 2, 99%, two – tailed b. z = 2, 95%, one – tailed, right c. z = -2.65, 95%, two – tailed d. z = 1.86, 99%, one – tailed e. z = -4.1, 95%, two – tailed f. z = 1.39, 99%, one – tailed What decision can you associate with the z – value if it is 1.69 at 95% confidence level, two tailed? 241 School Teacher Time and Date I. OBJECTIVES A. Content Standard B. Performance Standards C. Learning Competency II. III. CONTENT LEARNING RESOURCES A. References 1. Teacher’s Guide 2. Learners’ Materials 3. Reference Books 4. Additional Materials for Learning B. Other Learning Resources IV. Instructional Procedure Grade Level Learning Area Quarter 11 MATHEMATICS 3rd The learner demonstrates understanding of key concepts of test of hypothesis on the population mean and population proportion. The learner is able to perform appropriate tests of hypotheses involving the population mean and the population proportion to make inferences in real – life problems in different disciplines. M11/12 SP – IVf –g-1 Solves problems involving test of hypotheses on the population proportion. Performance Indicators: 3. Conduct tests involving population proportion; 4. Interpret test of proportions. Testing Hypothesis Involving Population Proportion Statistics and Probability by Belecina et. al. Statistics and Probability by Arciaga et. al. Review/ Motivation Ask students to give reactions on these statements. 242 1. Activity 1. When the evidence is not enough, do not reject the null hypothesis. 2. When the evidence is sufficient to reject the null hypothesis, a significant difference exists. (Teacher solicits reactions from the students and discusses with them that the two statements are true.) Teacher’s exposition and unlocking of difficulties. There are certain situations where inferences are to be made using only the proportions or percentages of population. These inferences are made in the context of probability- P. The formula for the test statistic z for proportions is ̂ 𝑝−𝑝 𝑧 = ̂̂ 0 ∝𝑝 Where 𝑥 𝑝̂ = 𝑛 𝑝_𝑜 = ℎ𝑦𝑝𝑜𝑡ℎ𝑒𝑠𝑖𝑧𝑒𝑑 𝑝𝑜𝑝𝑢𝑙𝑎𝑡𝑖𝑜𝑛 𝑝𝑟𝑜𝑝𝑜𝑟𝑡𝑖𝑜𝑛 , 𝑝 ∝ 𝑝̂ = 𝑝𝑞 √ 𝑛 𝑖𝑠 𝑡ℎ𝑒 𝑠𝑡𝑎𝑛𝑑𝑎𝑟𝑑 𝑑𝑒𝑣𝑖𝑎𝑡𝑖𝑜𝑛 𝑜𝑓 𝑡ℎ𝑒 𝑠𝑎𝑚𝑝𝑙𝑖𝑛𝑔 𝑑𝑖𝑠𝑡𝑟𝑖𝑏𝑢𝑡𝑜𝑛 𝑝̂ 𝑜𝑟 𝑝𝑜 𝑞𝑜 𝑛 ∝ 𝑝̂ = √ 𝑖𝑓 𝑝𝑜 𝑖𝑠 𝑢𝑠𝑒𝑑. 𝑞𝑜= 1 − 𝑝𝑜 So 𝑝̂−𝑝 𝑧 = 𝑝 𝑞𝑜 √ 𝑜𝑛 𝑜 For a one-tailed test: 𝐻𝑜: 𝑝 = 𝑝𝑜 𝐻1: 𝑃>𝑃𝑂 & the rejection region is 𝑧 > 𝑧∝ or 𝐻1:𝑃< 𝑃𝑂 & 𝑡ℎ𝑒 𝑟𝑒𝑗𝑒𝑐𝑡𝑖𝑜𝑛 𝑟𝑒𝑔𝑖𝑜𝑛 𝑖𝑠 𝑧 < −𝑧𝛼 For a two – tailed test 𝐻𝑜 : 𝑝 = 𝑝𝑂 𝐻1 : 𝑝 ≠ 𝑝𝑜 The rejection region is 𝑧 < −𝑧𝛼 𝑜𝑟 𝑧 > 𝑧𝛼 2 2 Recalling the previous table for critical values, Confidence Significance Critical Values level Level One -Tailed Two-Tailed . 05 (5%) . 95% ±1.65 ±1.96 . 01(1%) . 99% ±2.33 ±2.58 Students’ activity 1(student ’s task) In small groups of 3 members, let the students solve for z if: 𝑛 = 94 15 𝑝̂ = 94 𝑝𝑜 = 15 % (Call on a student volunteer to show solution on the board) Expected solution: 𝑝̂ − 𝑝𝑜 𝑧= 𝑝 𝑞 √ 𝑜 0 𝑛 243 15 − 15 𝑧 = 94 √(. 15)(. 85) 94 𝑧 ≈ 0.26 𝑞𝑜 = 1 − 𝑝𝑜 = 1- .15 = .85 Student’s Activity 2(Divided Problem Solving) Post the problem below : A whitening soap as product of factory A is claimed as 60% effective. A research was conducted to 100 adults and 70 of them found the soap effective. Can this fact be used to conclude that its product is more effective over the other whitening soap being sold in the leading store? Conduct a hypothesis test using the 0.05 level of significance. Divide the class into groups of 5 members & let each group work on solving the given problem using the guide questions/ directives below: 1. Is CLT applicable? Why? 2. What is the population parameter? 3. What are the given data? 4. Formulate the hypotheses. 5. Select the test statistic. 6. Compute using the test statistic. 7. State the decision rule. 8. Interpret the result. 2. Analysis (Call on a representative of each group to present the solution, one at a time.) Expected solution: 1. Is CLT applicable? Why? 2. What is the population parameter? 3. What are the given data? Yes, because 𝑛 > 30, n= 100 Population proportion p. 4. Formulate Hypotheses 𝐻0 : 𝑝̂ =𝑝0 244 𝑝̂ = 70%= .70 n= 100 𝑝𝑜 = 60%=. 60 𝑞𝑜 = 1 − 𝑝0 𝑞𝑜 = .40 𝐻1 : 𝑝̂ > 𝑝0 5. Select the test statistic Test Statistic: Z -test 𝑝̂ − 𝑝𝑜 𝑧= 𝑝 𝑞 √ 𝑜 𝑜 𝑛 𝑝̂ − 𝑝0 6. Compute using the 𝑧= test statistic √𝑝𝑜 𝑞𝑜 . 70 − .60 𝑧= √(. 60)(. 40) 100 = 2.041241452 ≈ 2.04 7. State the decision Z= 2.04 at 𝛼 = .05, the rule critical values are ± 1.65, right- tailed 2.04> 1.65 Z value lies in the rejection area Decision rule : reject the 𝐻𝑜 8. Interpret the result There is a significant difference between the two parameters compared. The whitening soap as a product of factory A is more effective than the other whitening soap being sold in the leading stores. Teacher’s exposition is essential in this part to guide and clarify salient concepts especially on the statement of the decision rule & interpretation parts. 3. Abstraction 4. Application (The teacher lead the class to formulate generalization ) Student’s activity Based from the previous activity and discussion, what are the suggested steps in solving problems involving test of hypotheses on the population or proportion? Expected answers: 1. Determine the given data. 2. Formulate the hypotheses. Let the test is directional or non directional . 3. Select the test Statistic 4. Compute for using the test statistic. 5. State the decision rule. 6. Interpret the results. Let the students work on the following problem in pairs, The supplier of a truckload of fruits asserts that less than 5% of these are with defects, 20 prone these assertion, 250 fruits were randomly selected, tested and were found to be with 245 defects is this sufficient to conclude that less than 5% of the fruits are with defects? Use 0.01 as significance level. (Call on 2 to 3 volunteers to present solution ) Expected answers: Given data: P= 0.05(5%)= 𝑝𝑜 ( given a null hypothesis) n= 200- CLT is applicable 10 𝑝̂ = = 0.04 250 𝛼 = 0.01; 𝑐𝑟𝑖𝑡𝑖𝑐𝑎𝑙 𝑣𝑎𝑙𝑢𝑒: 𝑙𝑒𝑓𝑡 ∶ −1.65 𝑞𝑜 = 1 − 𝑝𝑜 = 1-0.05 =.95 Hypotheses: 𝐻𝑂 = 𝑃 = 𝑃𝑂 = 0.05 𝐻1 : 𝑝 < 0.05 (𝑑𝑖𝑟𝑒𝑐𝑡𝑖𝑜𝑛𝑎𝑙 − 𝑙𝑒𝑓𝑡 − 𝑡𝑎𝑖𝑙𝑒𝑑) Test statistic: z statistic 𝑝̂−𝑝 𝑧 = 𝑝 𝑞𝑜 √ 𝑜𝑛 𝑂 = 0.04−0.05 (0.05)(0.95) 250 √ = -0.7254762501 ≈-0.73 Decision Rule Z= -0.73 Home Task (For Reflection) 246