Mixed Numbers and Improper Fractions Mood Rings, Part 1 ACTIVITY 1.6 SUGGESTED LEARNING STRATEGIES: Summarize/Paraphrase/ Retell, Vocabulary Organizer My Notes Tyrell and four of his friends from West Middle School went to a craft fair and they all decided to buy mood rings. When discussing their ring sizes with the ring maker, they learned about anthropometry. Did you know that the average length around a 1 inches and the average length woman’s ring finger is about 2 ___ 16 9 inches? around a man’s ring finger is about 2 ___ 16 Before they can buy their rings, the friends must first measure their ring fingers. Anthropometry is the study of the measurement of the human body in terms of its dimensions. People who design things for others to use, such as bracelets or rings, have to take typical body measurements into account. Jose 1 in. 2 __ 4 2 Nisha 3 in. 1__ 4 #1 #2 #3–4 Ema 3 in. 2 ___ 16 © 2010 College Board. All rights reserved. Remember, a mixed number is the sum of a whole number and a proper fraction. 2 1 3 1 inches? Count the __ 1 inches on 1 inches are in 2 __ b. How many __ 2 2 2 the diagram and write your answer as an improper fraction. 0 2 1 MATH TERMS A positive improper fraction has a value greater than or equal to 1. The numerator is greater than or equal to the denominator. 3 __5 in. 2 c. Another way to see this is to use a model. Name the shaded parts of this diagram two ways. 1 2 __ 2 Mixed Number: ______ (wholes + part) 1 The purpose of this question is to engage students in the context of the activity by making a personal connection. Students may need a review mini-lesson on 1 inch. measuring to the nearest ___ 16 2 Vocabulary Organizer (a, b) This begins a series of four questions that serve as a review of writing mixed numbers and improper fractions using pictures, number lines, and abstract rules. __5 2 Improper Fraction: ______ (total parts) Unit 1 • Number Concepts 033-038_SB_MS1_1-6_SE.indd 33 © 2010 College Board. All rights reserved. #5 #13–14 #6–11 #12 Paragraph Summarize/Paraphrase/Retell a. Look at this measuring tape to determine Bob’s finger size. Write your answer as a mixed number in the table above. 0 Materials Chunking the Activity 2. This table shows the finger sizes of the five friends. 1 in. 2 __ • Converting between mixed numbers and improper fractions • Comparing and ordering mixed numbers and improper fractions • Measuring tapes (at least 1 per pair of students) • Fraction circles/bars (optional) Answers may vary. Sample answer: Ring sizes should vary 3 inches. 1 to 2 __ roughly from 1 __ 2 4 Bob Mixed Numbers and Improper Fractions Activity Focus CONNECT TO SCIENCE 1. How big is your ring finger? To measure your ring finger wrap a measuring tape snugly around the base of your finger. Record 1 of an inch. your measurement to the nearest ___ 16 Tyrell 7 in. 1__ 8 ACTIVITY 1.6 Investigative 33 12/16/09 5:44:44 PM 1 Inch MINI-LESSON: Measuring to the Nearest ___ 16 Give each student a long strip of paper. Have students draw a line at each end of their strips and label the left side 0 and the right side 1, 1. then fold their strips in half and at the top label this crease, __ 2 Students fold their strips in half again and label each crease now with _14_, _2_, just below the label for _1_, and _3_. Have students do this two more 4 2 1 4’s. Encourage students to use different times in order to create _18_’s and ___ 16 sized lines when labeling the creases. Compare the strips students create to a standard ruler. Let students practice measuring objects to the 1 units of their “rulers.” nearest _12_, _14_, _18_, and ___ 16 Unit 1 • Number Concepts 33 ACTIVITY 1.6 Continued ACTIVITY 1.6 continued Mixed Numbers and Improper Fractions Mood Rings: Part 1 2 (continued) Think/Pair/ Share, Look for a Pattern (f), Quickwrite (f) Stress the relationships between the parts so that students understand why the “trick,” or algorithm, works, and do not simply memorize a process. Students may need a vocabulary reminder on the following terms: quotient 3r1 __ _1 dividend divisor 2 7 -6 remainder 1 SUGGESTED LEARNING STRATEGIES: Think/Pair/Share, Look for a Pattern, Quickwrite, Create Representations My Notes d. Complete this description of how to find the improper fraction for the number of shaded halves: 2 shaded 2 whole shaded circles with ____ There are ____ 4 shaded halves. Plus, there halves in each. This gives me ____ 5 1 shaded half in the last circle, making a total of ____ is ____ shaded halves. e. Both the mixed number and the improper fraction in Part c describe the same number. Write an equation that shows the two are equal. 5 1 = __ 2 __ 2 2 f. Without drawing a model, describe a method to use the digits from the mixed number to find its equivalent improper fraction. (Hint: Consider your description in Part d.) 3 Create Representations Answers may vary. Sample answer: Multiply the denominator by the whole number to get 2 × 2 = 4, then add the numera5. tor to get 4 + 1 = 5. Put 5 over the denominator to get __ 2 3. Now convert Nisha’s finger size to an improper fraction. a. Use circles: __7 4 0 1 © 2010 College Board. All rights reserved. b. Use a number line: 2 __7 4 c. Use the method you discovered in Part e of Question 2. Did you get the same answer as you did in Parts a and b? __7 ; yes 4 4. Use your method from Question 2e to convert the other friends’ sizes to improper fractions. a. Tyrell b. Ema c. Jose 15 ___ 8 35 ___ 16 __9 4 34 SpringBoard® Mathematics with Meaning™ Level 1 0 12/16/09 5:44:48 P © 2010 College Board. All rights reserved. 033-038_SB_MS1_1-6_SE.indd 34 34 SpringBoard® Mathematics with Meaning™ Level 1 Mixed Numbers and Improper Fractions ACTIVITY 1.6 Mood Rings: Part 1 continued ACTIVITY 1.6 Continued 5 Identify a Subtask, Debriefing SUGGESTED LEARNING STRATEGIES: Identify a Subtask, Quickwrite My Notes 5. You can use two methods to change from an improper fraction to a mixed number: drawing a model or dividing. 9 . Then write a mixed number to represent a. Draw a model of __ 4 the whole and fractional parts of your model. Suggested Assignment CHECK YOUR UNDERSTANDING p. 38, #1 WRITING MATH A fraction is a way of writing a division problem: 9 __ = 9 ÷ 4. 4 UNIT 1 PRACTICE p. 59, #40–41 1 2 __ 4 6 Quickwrite Students are b. Divide 9 by 4. Express the remainder as a fraction to get a mixed number. expected to use prior knowledge and compare the whole numbers. 1 9 ÷ 4 = 2 __ 4 7 Quickwrite Students compare The five friends want to compare finger sizes to see whose ring finger is the largest and whose is the smallest. the unit fractions using prior knowledge—the smaller the denominator, the bigger the unit fraction. 6. Nisha and Jose compare their finger sizes. Write an inequality symbol in the circle to make the statement true. Explain your thinking. Nisha 3 1__ 4 < Jose 1 2__ 4 8 Quickwrite Students use knowledge from Activity 1.5 to solve this problem. Make a quick informal assessment using anecdotal records to identify students in need of reteaching for comparing fractions. © 2010 College Board. All rights reserved. Explanations may vary. Sample answer: Jose; the whole 3 < 2 __ 1. numbers are different so I compare them: 1 < 2, so 1 __ 4 4 7. Next, Bob and Jose compare. Which of them has the larger ring finger? Explain your thinking. Bob 1 2 __ 2 > Jose 1 2 __ 4 Encourage students to share and compare their different approaches. Explanations may vary. Sample answer: Bob; the whole 1 and __ 1 are numbers are the same so I compare the fractions. __ 2 4 1 1. unit fractions, and halves are bigger than fourths, so 2 __ > 2 __ 2 4 3 and 1 __ 7 . Whose 8. Then Nisha and Tyrell compare their sizes of 1 __ 4 8 finger is larger? Express your answer as an inequality. Explain your thinking. 3 . Students’ explanations may 7 > 1 __ Tyrell’s finger is larger: 1 __ 8 4 vary depending on the process they choose to arrive at their answers. Unit 1 • Number Concepts 12/16/09 5:44:53 PM © 2010 College Board. All rights reserved. PM 033-038_SB_MS1_1-6_SE.indd 35 35 Unit 1 • Number Concepts 35 9 Think/Pair/Share, Quickwrite (b) Students should write names and sizes. They then compare Ema to Jose and see 4 would be equal to _1_ which that ___ 4 16 is Jose’s fraction, so Ema’s size is 3 . smaller, as her fraction is ___ 16 Students know Ema’s finger size is bigger than Tyrell’s though because her mixed number has a whole number of 2. ACTIVITY 1.6 continued Mixed Numbers and Improper Fractions Mood Rings: Part 1 SUGGESTED LEARNING STRATEGIES: Quickwrite, Think/ Pair/Share, Create Representations, Debriefing My Notes 9. You have compared the sizes of four friends, two at a time. a. Use what you have learned to order the friends by their ring finger sizes, going from smallest to largest. Nisha, Tyrell, Jose, Bob b. Where does Ema fit into this order? Explain. Ema fits in between Tyrell and Jose. 10. Ema tells her friends that they could order their fractions all at once by using common denominators. Show how this can be done. Change the mixed numbers to improper fractions with 0 The purpose of this question is for students to discover that they can use common denominators to compare multiple fractions at the same time. 15 = ___ 30 ; Bob: 2 __ 5 = ___ 40 ; 7 = ___ 1 = __ 16 as the denominator. Tyrell: 1 __ 8 8 16 2 2 16 9 = ___ 36 ; Nisha: 1__ 3 = __ 28 ; Ema: 2 ___ 3 = ___ 35 ; then 1 = __ 7 = ___ Jose: 2 __ 4 4 16 4 4 16 16 16 compare the numerators to find that the order from smallest to largest is Nisha, Tyrell, Ema, Jose, and Bob. a Create Representations, Debriefing Students practice ordering on a number line as another way of ordering. Be sure students are plotting points and not shading the line. b Create Representations, Quickwrite, Think/Pair/ Share This question is meant to give students the opportunity to think about a variety of possibilities and decide how they can use what they already know to answer the questions. 11. Order the friends’ ring finger sizes from least to greatest on the number line below. Label each point with each person’s initial as shown for Bob. N T 1 CONNECT TO AP Looking at the pattern of points on a number line can help you decide if the numbers are getting close to a particular number. Discovering such patterns is a fundamental concept in advanced math courses. EJ B 2 3 © 2010 College Board. All rights reserved. ACTIVITY 1.6 Continued 12. You now know different ways to order measurements. How would you order the measurements of several other friends? Describe your method. Karen Ahmed Ileana Keisha Hunter 5 1__ 7 __ 5 2 ___ 4 __ 14 ___ 8 4 16 2 8 Answers may vary. Sample answer: First change all numbers to either mixed numbers or improper fractions, and then compare them as done earlier. The finger sizes are easy to order since the fractions are all 1 ’s, or ___ 1 ’s, __ 1 ’s, like the increments on a ruler. However, 1 ’s, __ in __ 2 4 8 16 98 , 1 ___ 23 , and 2 ___ 15 , 2 ____ 2 , do not have many numbers, such as 1___ 31 100 44 71 denominators that are as simple to compare. 36 SpringBoard® Mathematics with Meaning™ Level 1 Connect to AP Students will need to be able to graph and order fractions on a number line or in the coordinate plane when they study sequences and series, especially, those that converge to a real number. Consider the sequence 3 __ 9 99 1 , __ 2 , __ __ , 4 , …, ___ , … ____ , …. Have your class graph these fractions on a 2 3 4 5 10 100 number line. They can then observe that the points are getting closer and closer to the number 1. However, no number in the sequence will ever equal 1 or be greater than 1. An activity like this will set the stage for future understanding of limits, a fundamental concept in calculus. 36 SpringBoard® Mathematics with Meaning™ Level 1 12/16/09 5:44:58 P 0 © 2010 College Board. All rights reserved. 033-038_SB_MS1_1-6_SE.indd 36 Mixed Numbers and Improper Fractions ACTIVITY 1.6 Mood Rings: Part 1 continued SUGGESTED LEARNING STRATEGIES: Summarize/Paraphrase/ Retell, Create Representations, Quickwrite, Debriefing, Self Revision/Peer Revision To order numbers like these, think about how close each fraction 1 , 1, and so on. For example, is to benchmark numbers, such as 0, __ 2 15 15 1 ___ __ 1 is a little less than 1 , because half of 32 is 16. Thus, place 1___ 31 2 31 1 __ just before the 1 mark. 2 1 23 44 1 15 1 31 22 71 R Read and Think Aloud is a good teacher strategy wh reading the informato use while tion before Question 13. TEACHER TO TEACHER My Notes MATH TERMS Benchmark numbers are numbers used as points of comparison when estimating. Paragraph Summarize/Paraphrase/Retell 2 98 100 2 C Create Representations 98 Students reason that 2____ is just 23 100 ___ a little less than 3, 1 44 is a little greater than 1_12_ because _12_ of 44 2 is a little greater is 22, and 2___ 71 than 2 but less than 2_12_. 3 23 , and 2 ___ 98 , 1 ___ 2 on 13. Continue using benchmarks to order 2 ____ 100 44 71 the number line above. 14. Summarize your findings on comparing and ordering mixed numbers and improper fractions by discussing the following cases. d Quickwrite, Debriefing, Self Revision/Peer Revision Students form generalizations for comparing and ordering different combinations of mixed numbers and improper fractions. 3 and 3 ___ 1 a. Whole numbers are different: 2 ___ 19 27 Answers may vary. Sample answer: Just compare the whole numbers. The bigger the whole number, the bigger the mixed number. Suggested Assignment 7 2 and 5 __ b. Whole numbers are the same: 5 __ 3 9 © 2010 College Board. All rights reserved. ACTIVITY 1.6 Continued CHECK YOUR UNDERSTANDING p. 38, #2–7 Answers may vary. Sample answer: Compare the fractions by either writing equivalent fractions or using crossmultiplication. UNIT 1 PRACTICE p. 59, #42–44 32 and ___ 27 c. Both are improper fractions: ___ 5 4 Answers may vary. Sample answer: Compare them the same way you compare common fractions. 13 3 and ___ d. One mixed number and one improper fraction: 6 __ 5 2 Answers may vary. Sample answer: Either change the improper fraction to a mixed number or the mixed number to an improper fraction, then solve using the methods discussed earlier. Unit 1 • Number Concepts 12/16/09 5:45:01 PM © 2010 College Board. All rights reserved. PM 033-038_SB_MS1_1-6_SE.indd 37 37 Unit 1 • Number Concepts 37 ACTIVITY 1.6 Continued ACTIVITY 1.6 continued Mixed Numbers and Improper Fractions Mood Rings: Part 1 Answer Key 5 b. 5__ 9 2. Kendra, Miley, Bryson, Wyatt 3. Juan 4. See answer to #4 below. 9 47 5a. 8___ > ___ 11 6 53 3 b. ___ < 7__ 7 5 6 7 , 3 ___ 11 , ___ 24 , 4 __ 6. __ 7 2 20 5 7. Answers may vary. Sample answer: Fractions can be expressed as proper fractions, improper fractions, or mixed numbers. Comparing mixed numbers and improper fractions is like comparing proper fractions because you can find equivalent fractions if you need to and then use common denominators or common numerators to compare; comparing mixed numbers and improper fractions is different from comparing proper fractions because with mixed numbers sometimes you can just compare the whole number parts and sometimes you have to convert the mixed number to an improper fraction. CHECK YOUR UNDERSTANDING Write your answers answers on on notebook notebook paper. paper.Show your work. 4. Order each of the following numbers Show your work. by placing them on a number line. Use benchmark numbers to determine their 1. Convert the improper fraction to a mixed placement. number and the mixed number to an 10 , and __ 8 2 , ___ 11 , 2 __ 1___ 20 5 7 3 5. Compare. improper fraction. 50 4 a. 7 __ b. ___ 7 9 2. Mr. White’s students are playing a game. He gives each student in a group a fraction to help them decide the order in which they will play. The person with the largest fraction goes first, and so on. The table below shows the fractions for the students in one group. Wyatt 3 1__ 4 Kendra 8 2 ___ 11 Miley 19 ___ 7 9 and ___ 3 53 and 7 __ 47 b. ___ a. 8 ___ 7 5 11 6 6. Order from least to greatest: 6 , ___ 7 , 3 ___ 24 , __ 11 4 __ 7 5 2 20 7. MATHEMATICAL Describe the three forms R E F L E C T I O N in which fractions can be written. Explain how to compare the three forms. Give examples using different forms of fractions. Bryson 9 __ 5 List the order in which they will take their turns. © 2010 College Board. All rights reserved. 53 1a. ___ 7 3. Kim and Juan are measuring their wrists to 5 in. purchase watches. Kim’s measures 5 __ 8 3 __ and Juan’s measures 5 in. Who has the 4 larger wrist? 38 SpringBoard® Mathematics with Meaning™ Level 1 12/16/09 5:45:04 P 4. 1 38 SpringBoard® Mathematics with Meaning™ Level 1 10 111 7 20 2 22 5 8 3 3 © 2010 College Board. All rights reserved. 033-038_SB_MS1_1-6_SE.indd 38