3rd Grade Comprehensive CRCT Math Study Guide Content Weights: Number Operations-55%, Measurement-23%, Geometry-10%, Algebra-7%, Data Analysis & Probability-5% Number and Operations: 55% = 33 questions Number and Operations: Students will use decimal fractions and common fractions to represent parts of a whole. They will also understand the four arithmetic operations for whole numbers and use them in basic calculations, and apply them in problem solving situations. M3N1 Students will further develop their understanding of whole numbers and decimals and ways of representing them. a. Identify place values from tenths through ten thousands. b. Understand the relative sizes of digits in place value notation (10 times, 100 times, 1/10 of a single digit whole number) and always to represent them including word name, standard form and expanded form. Place Value through the ten thousands. Thousands tens ones 2 7 Ones hundreds tens ones 5 6 9 , Each group of 3 digits separated by a comma in a number is called a period. vocabulary digit place value standard form expanded form word form definition Any one of the ten number symbols The value of a digit determined by its place in a number The usual, or common, way of writing a number, using digits A way of writing a number as the sum of the values of the digits A way of writing a number using words Whole numbers Ten thousands thousands 7 Standard form Expanded form Word form example 1 , 0,1,2,3,4,5,6,7,8, or 9 The value of the 2 in the number 27,569 is 20,000 27,569 20,000 + 7,000 + 500 + 60 + 9 Twenty-seven thousand, five hundred sixty-nine (and is only used when there is a decimal point) hundreds tens 3 8 Decimals ones Tenths Hundredths 1 1 10 100 or or 1.0 0.1 0.01 2 . 2 1 71, 382.21 70,000+1,000+300+80+2+ .2+ .01 seventy-one thousand, three hundred eighty-two and twenty-one hundredths 1 M3N2 Students will further develop their skills of addition and subtraction and apply them in problem solving. a. Use the properties of addition and subtraction to compute and verify the results of computation. b. Use mental math and estimation strategies to add and subtract. c. Solve problems requiring addition and subtraction. d. Model addition and subtraction by counting back change using the fewest number of coins. Properties of Addition Commutative property: When two numbers are added, the sum is the same regardless of the order of the addends. For example 4 + 2 = 2 + 4 Associative Property: When three or more numbers are added, the sum is the same regardless of the grouping of the addends. For example (2 + 3) + 4 = 2 + (3 + 4) Identity Property: The sum of any number and zero is the original number. For example 5 + 0 = 5. There is an inverse relationship between addition and subtraction. Example: Since 3 + 7 = 10 then the following are also true: 10 - 3 = 7 10 - 7 = 3 Similar relationships exist for subtraction. Example: Since 10 - 3 = 7 then the following are also true: 3 + 7 = 10 7 + 3 = 10 An equation is balanced or the same on either side of the equals (=) sign. If exactly the same thing is done to both sides of the equation, it will still be balanced or equal. In the example above we start with the equation 3 + 7 = 10: Subtract the same number from both sides 3 + 7 - 3 = 10 - 3 On the left side the 3 and -3 produce 0 which leaves 7 = 10 - 3 Turning the equation around to be in more normal form 10 - 3 = 7 2 M3N3 Students will further develop their understanding of multiplication of whole numbers and develop the ability to apply it in problem solving. a. Describe the relationship between addition and multiplication, i.e., multiplication is defined as repeated addition. For example, 3 x 7 = 21, instead you may consider it as 3 x 7 = 7 + 7 + 7 = 14 + 7 = 21. This particular method is a bit challenging in terms of addition for a child, but it lucidly shows the relationship between multiplication and addition. Accordingly, you may also calculate 9 x 7 = 10 x 7 - 7 = 63 or 6 x 7 = 3 x 7 + 3 x 7 = 21 + 21 = 42. It is also a creative method to learn the multiplication table, which explains you the exact working of math. b. Know the multiplication facts with understanding and fluency to 10x10. × 1 2 3 4 5 6 7 8 9 10 11 12 1 1 2 3 4 5 6 7 8 9 10 11 12 2 2 4 6 8 10 12 14 16 18 20 22 24 3 3 6 9 12 15 18 21 24 27 30 33 36 4 4 8 12 16 20 24 28 32 36 40 44 48 5 5 10 15 20 25 30 35 40 45 50 55 60 6 6 12 18 24 30 36 42 48 54 60 66 72 7 7 14 21 28 35 42 49 56 63 70 77 84 8 8 16 24 32 40 48 56 64 72 80 88 96 9 9 18 27 36 45 54 63 72 81 90 99 108 10 10 20 30 40 50 60 70 80 90 100 110 120 11 11 22 33 44 55 66 77 88 99 110 121 132 12 12 24 36 48 60 72 84 96 108 120 132 144 3 Multiplication by a single digit 23 x 4 23 is 2 tens and 3 ones. 3 ones multiplied by 4 gives 12 ones and 2 tens multiplied by 4 gives 8 tens (that is 80). 80 and 12 are added to give the final product 92. The 3 ones are first multiplied by 4 giving the product 12, which is 1 ten and 2 ones. 2 is written in the ones column and the 1 is recorded in the tens column. Now the 2 tens are multiplied by 4 to give 8 tens. The 1 ten recorded before is added on, so the product has 9 tens. M3N3 c. Use arrays and area models to develop understanding of the distributive property and to determine partial products for multiplication of 2- or 3- digit number. Multiplication can be defined in terms of repeated addition. For example, 3 × 6 can be viewed as 6 + 6 + 6. More generally, for any positive integer n, n × b can be represented as n × b = b + b + … + b where the sum on the right consists of n addends. A rectangular array provides a visual model for multiplication. For example, the product 3 × 6 can be represented as By displaying 18 dots as 3 rows with 6 dots in each row, this array provides a visual representation of 3 × 6 as 6 + 6 + 6. An equivalent area model can be made in which the dots of the array are replaced by unit squares. 4 Besides representing 3 × 6 as an array of 18 unit squares, this model also shows that the area of a rectangle with a height of 3 units and a base of 6 units is 3 × 6 square units, or 18 square units. Given a pair of numbers a and b called factors, multiplication assigns them a value a × b = c, called their product. The Commutative Property of Multiplication states that changing the order in which two numbers are multiplied does not change the product. That is, for all numbers a and b, a × b = b × a. The array model can be used to make this plausible. For example, because 3 × 6 = 6 × 3, an array with 3 rows and 6 dots in each row has the same number of dots as an array with 6 rows and 3 dots in each row. Another important property of multiplication is the Identity Property of Multiplication. It states that the product of any number and 1 is that number. That is, for all numbers a, a × 1 = 1 × a = a. The Zero Property of Multiplication states that when a number is multiplied by zero, the product is zero. That is, for all numbers a, a × 0 = 0 × a = 0. M3N3 d. Understand the effect on the product when multiplying by multiples of 10. 8x1=8 8x2=16 8x10=80 8x2=160 8x100=800 8x200=1600 8x1000=8,000 8x2000=16,00 e. Apply the identity and commutative and associative properties of multiplication and verify the results. Multiplication Property definition Example When you change the order of the 5x4 = 4x5 Commutative Property factors, the product stays the same. When you group factors in different (6 x 7) x 9 = 6 x (7 x 9) Associative Property ways, the product stays the same. The parentheses tell you which numbers to multiply first. When two addends are multiplied by a Distributive Property factor, the product is the same when (3 + 5) x 2 = (3 x 2) + (5 x 2) each addend is multiplied by the factor and those products are added. 5 Property of One Zero Property When you multiply any number by 1, the product is equal to that number. When you multiply any number by 0, the product is 0. Factor–the number used in a multiplication problem: Product-the answer in a multiplication problem: Addend-the number to be added in an addition problem: 6 x 5 = 30 6 x 5 = 30 (3+5) x 2 12 x 1 = 12 178 x 0 = 0 6 and 5 are factors 30 is the product 3 and 5 are addends f. Use mental math and estimation strategies to multiply. g. Solve problems requiring multiplication. M3N4 Students will understand the meaning of division and develop the ability to apply it in problem solving. a. Understand the relationship between division and multiplication and between division and subtraction. b. Recognize that division may be two situations: the first is determining how many equal parts of a given size or amount may be taken away from the whole as in repeated subtraction, and the second is determining the size of the parts when the whole is separated into a given number of equal parts as in a sharing model c. Recognize problem-solving situations in which division may be applied and write corresponding mathematical expressions. When you divide to find the number of objects in each group, the division is called fair sharing or partitioning. For example: A farmer is filling baskets of apples. The farmer has 24 apples and 4 baskets. If she divides them equally, how many apples will she put in each basket? When you divide to find the number of groups, the division is called measuring or repeated subtraction. It is easy to see that you can keep subtracting 4 from 24 until you reach zero. Each 4 you subtract is a group or basket. A farmer has 24 apples. She wants to sell them at 4 apples for $1.00. How many baskets of 4 can she fill? Manipulatives and visual aids are important when teaching multiplication and division. Students have used arrays to illustrate the multiplication process. Arrays can also illustrate division. 6 Since division is the inverse, or opposite, of multiplication, you can use arrays to help students understand how multiplication and division are related. If in multiplication we find the product of two factors, in division we find the missing factor if the other factor and the product are known. In the multiplication model below, you multiply to find the number of counters in all. In the division model you divide to find the number of counters in each group. The same three numbers are used. The model shows that division “undoes” multiplication and multiplication “undoes” division. So when multiplying or dividing, students can use a fact from the inverse operation. For example, since you know that 4 x 5 = 20, you also know the related division fact 20 ÷ 4 = 5 or 20 ÷ 5 = 4. Students can also check their work by using the inverse operation. Notice that the numbers in multiplication and division sentences have special names. In multiplication the numbers you multiply are called factors; the answer is called the product. In division the number being divided is the dividend, the number that divides it is the divisor, and the answer is the quotient. Discuss the relationship of these numbers as you explain how multiplication and division are related. There are other models your students can use to explore the relationship between multiplication and division. Expose your students to the different models and let each student choose which model is most helpful to him or her. Here is an example using counters to multiply and divide. 7 factor 4 number of groups dividend 12 total number of counters x factor 3 counters in each group ÷ divisor 4 number of groups = product 12 total number of counters = quotient 3 counters in each group Here is an example using a number line. factor 4 x factor 5 = product 20 dividend 20 ÷ divisor 5 = quotient 4 Another strategy your students may find helpful is using a related multiplication fact to divide. The lesson Relating Multiplication and Division focuses on this strategy. Here is an example. 18 ÷ 6 = ? Think: 6 x ? = 18 Six times what number is 18? 6 x 3 = 18, so 18 ÷ 6 = 3. When students understand the concept of division, they can proceed to explore the rules for dividing with 0 and 1. Lead students to discover the rules themselves by having them use counters to model the division. A few examples follow. 8 Divide 4 counters into 4 groups. 4÷4=1 Divide 2 counters into 2 groups. 2÷2=1 When any number except 0 is divided by itself, the quotient is 1. Put 3 counters in 1 group. Put 5 counters in 1 group. 3÷1=3 5÷1=5 When any number is divided by 1, the quotient is that number. Divide 0 counters into 2 groups. 0÷2=0 Divide 0 counters into 4 groups. 0÷4=0 When 0 is divided by any number except 0, the quotient is 0. Divide 6 counters into 0 groups. Divide 1 counter into 0 groups. You cannot divide a number by 0. 9 Encourage students to think about the relationship between multiplication and division when they solve problems. For example, they can use a related multiplication fact to find the unit cost of an item—for example the cost of one baseball cap priced at 3 for $18. $18 ÷ 3 = $6 Think: 3 x ? = $18 3 x $6 = $18 So $18 ÷ 3 = ? The cost is $6 for one baseball cap. Dividing by Repeated Subtractions The result of division is to separate a group of objects into several equal smaller groups. The starting group is called the dividend. The number of groups that are separated out is called the divisor. The number of objects in each smaller group is called the quotient. ex: 24 divided by 6 (24 / 6 = 4) 24 is the Dividend 6 is the divisor and the quotient is 4 Which means 24 can be divided into 4 equal parts of 6 each. The results of division can be obtained by repeated subtraction. If we are separating 24 objects into 4 equal groups of six, we would take (or subtract) six objects at a time from the large group and place them in 4 equal groups. In mathematical terms this would be: 24-6-6-6-6. M3N4 d. e. f. g. Explain the meaning of a remainder in division in different circumstances. Divide a 2- and 3- digit number by a 1- digit divisor. Solve problems requiring division. Use mental math strategies to divide. If you divide 13 bananas evenly between Joe and Sally, how much does each one get? 13 ÷ 2 = ? We say that Joe and Sally both get 6 bananas and one is left over. The leftover banana is called the remainder. Or, if we don't want leftovers or remainders, both would get 6 1/2 bananas. 13 ÷ 2 = 6, remainder 1. 10 14 bananas divided between 3 people gives 4 bananas to each and 2 bananas that cannot be divided. 14 ÷ 3 = 4, remainder 2 8 scissors divided between 5 people gives 1 scissors to each and 3 scissors that cannot be divided. 8 ÷ 5= 1, remainder 3 Division Steps There are five steps of dividing to remember. 1. Divide. 2. Multiply. 3. Subtract. 4. Compare. 5. Long Division 4 -- Quotient Divisor -- 3 |12 -- Dividend Bring down the next number. 11 1 6|84 1 1. Divide 84 ÷ 6 is the problem. Look at the first number only in the dividend so the problem is 8 ÷ 6. The answer is 1. Write it above the 8. 2. Multiply. 1 x 6 = 6. Write the number 6 under the 8. 6|84 6 3. 1 4. 6|84 -6 2 5. Subtract. 8 - 6. The answer is 2. Write it down under the 6 Compare what is left over after subtracting with the divisor. It must be less than the divisor, if not, then go back to step 1 and choose a larger number to multiple. Bring down the 4. Then go through steps 1 through 4 again. 24 ÷ 6 = 4. Multiple. Subtract. Compare. There is not another number to bring down. The final answer is 14. 84 ÷ 6 = 14. 14 6|84 -6 24 -24 0 M3N5 Students will understand the meaning of decimal fractions and common fractions in simple cases and apply them in problem-solving situations. a. Identify fractions that are decimal fractions and/or common fractions. b. Understand that a common fraction (i.e., 3/10) can be written as a decimal (i.e. 0.3) 8 8= One decimal digit; one 0 in the denominator. 10 8 .08 = Two decimal digits; two 0's in the denominator. 100 8 .008 = 1000 Three decimal digits; three 0's in the denominator 12 c. Understand the fraction a/b represents an equal sized parts of a whole that is divided into b equal sized parts. d. Know and use decimal fractions and common fractions to represent the size of parts created by equal divisions of a whole. To show half, draw 2 equal boxes to represent the total number of equal parts and shade 1 part out of the 2 equal parts. Similarly, to show one-third, draw 3 equal boxes to represent the total number of equal parts and shade 1 part out of the 3 equal parts. To show three-quarters, draw 4 equal boxes to represent the total number of equal parts and shade 3 parts out of the 4 equal parts. e. Understand the concept of addition and subtraction of decimal fractions and common fractions with like denominators. f. Model addition and subtraction of decimal fractions and common fractions with like denominators. g. Use mental math and estimation strategies to add and subtract decimal fractions with like denominators. h. Solve problems involving decimal fractions and common fractions with like denominators. ADDING OR SUBTRACTING FRACTIONS WITH THE SAME DENOMINATORS Adding or subtracting fractions with the same denominator is easy. All you have to do is to add or subtract the numerators. And it is always a good idea to make your result "nice" by converting it to a mixed number and simplifying if possible. 13 Example: Find 1 2 + 5 5 Both fractions have the same denominator of 5, so we can simply add the numerators: 1 2 3 + = 5 5 5 1 5 + 2 5 = 3 5 Example: Find 7 3 8 8 Both fractions have the same denominator of 8, so we can simply subtract the numerators: 7 3 4 1 - = = 8 8 8 2 NOTE that the result was simplified (the numerator and the denominator divided by 4). 7 8 - 3 8 = 4 8 = 1 2 14 Measurement: 23% =14 questions Students will understand and measure time and length. They will also model and calculate perimeter and area of simple geometric figures. M3M1 Students will further develop their understanding of the concept of time by determining elapsed time of a full, half and quarter-hour. Start End Elapsed Time? 0:00 Time Time Start End Elapsed Time? 1:30 Time Time Start End Elapsed Time? 1:00 Time Time Start End Elapsed Time? 4:30 Time Time 15 Start End Elapsed Time? 1:00 Time Time Start End Elapsed Time? 2:15 Time Time Start End Elapsed Time? 2:15 Time Time Start End Elapsed Time? 2:30 Time Time 16 Start End Elapsed Time? 2:00 Time Time Start End Elapsed Time? 4:00 Time Time Start End Elapsed Time? 0:00 Time Time Start End Elapsed Time? 2:00 Time Time M3M2 Students will measure length choosing appropriate units and tools. a. Use the units, kilometer (km) and mile (mi.) to discuss the measure of long distances. b. Measure to the nearest ¼ inch, ½ inch and millimeter (mm) in addition to the previously learned inch, foot, yard, centimeter, and meter. 17 c. Estimate length and represent it using appropriate units. d. Compare one unit to another within a single system of measurement. Units of Length When measuring length in the customary system the common units used are inches, feet, yards, and miles. Units of length measure height, width, length, depth, and distance. People use "feet" to measure their height. Construction worker and architects use feet to measure walls, floors, and ceilings. It is also used to determine one point to another. The end of your thumb to your first joint is about 1 inch long. An egg carton is about a foot long. A standard doorway is about a yard in width. A man six-feet tall is 2 yards high. Distances between cities are measured in miles From smallest to greatest length measurements are compared as: Inches Feet Yards Miles Reading a Ruler When reading a ruler, you want to find out how far the item is from zero. When reading a ruler, you must locate the zero marking, this may vary depending on the ruler. On some rulers, the zeros start at the end, but on others it starts about 1/4 of an inch from the end. If you do not check your ruler beforehand you will not be getting an accurate measurement. Point A is 1 1/4 inches or 1 1/4 inches away from zero. Point B is 3 3/4 inches or 3 3/4 inches away from zero. Point C is 4 1/8 inches or 4 1/8 inches away from zero. 18 Customary Metric inch - in foot - ft yard - yd mile - mi 1 ft = 12 in 1 yd = 36 in 1 yd = 3 ft 1 mi=63,360 in 1 mi = 5280 ft 1 mi=1760 yd centimeter cm decimeter dm meter - m kilometer - km 1 cm=10 mm 1 dm=100 mm 1 dm=10 cm 1 m= 1000 mm 1 m=100 cm 1 m=10dm 1 km=1,000,000 mm 1 km=100,000 cm 1 km=10,000 dm 1 km=1000 m A paperclip is approximately 1 centimeter wide. A crayon is approximately 1 decimeter long. The distance from the floor to the door knob is approximately 1 meter. The length of 6 city blocks is approximately 1 kilometer long. Length The distance between the knuckles on your index finger is approximately 1 inch. ounce - oz Your notebook is approximately 1 foot tall. A baseball bat is approximately 1 yard long. Long distances are measured in miles. The distance a vehicle travels is measured in miles. pound - lb ton - T 1 lb = 16 oz 1 T = 32,000 oz 1 T = 2000 lb gram kilogram 1 kilogram = 1000 grams Weight A slice a bread weighs about 1 ounce. cups - c A loaf of bread weighs about 1 pound. A car weighs about 1 ton. pint - pt quarts - qt gallon - gal 1 pt = 2 c 1 qt = 4 c 1 qt = 2 pt 1 gal = 16 c 1 gal = 8 pt 1 gal = 4 qt Oil comes in a quart-sized container. A large container of milk comes in a 1 gallon container. A packet of sugar weighs about 1 gram. A car weighs about 1000 kilograms. A book weighs about 1 kilogram. milliliter - ml liter - l 1 liter = 1000 milliliters Capacity A small cup of coffee holds approximately 1 cup. A tall glass of lemonade or a bowl of soup holds approximately 1 pint. A bottle of cola is one liter. A very large bottle holds 3 liters. Ten drops from a medicine dropper is approximately 1 milliliter. When converting any unit of measurements if you want: To change to a larger unit, divide. To change to a smaller unit, multiply. 19 M3M3 Students will understand and measure the perimeter of geometric figures. a. Understand the meaning of linear unit and measurement in perimeter. b. Understand the concept of perimeter as being the length of the boundary of a geometric figure. c. Determine the perimeter of a geometric figure by measuring and summing the lengths of the sides. M3M4 Students will understand and measure the area of simple geometric figures (squares and rectangles). a. Understand the meaning of the square unit and measurement in area. b. Model (by tiling) the area of a simple geometric figure using square units (square inch, square foot, etc.) c. Determine the area of squares and rectangles by counting, addition, and multiplication with models. \Surface Area and Perimeter of a Rectangle The area of other squares can be found by counting squares or by multiplying the length of the sides. 20 The perimeter of a square is the total length of the four sides. Area of a Square If l is the side-length of a square, the area of the square is l2 or l × l. What is the area of a square having side-length 3.4? The area is the square of the side-length, which is 3.4 × 3.4 = 11.56. Area of a Rectangle The area of a rectangle is the product of its width and length. What is the area of a rectangle having a length of 6 and a width of 2.2? The area is the product of these two side-lengths, which is 6 × 2.2 = 13 21 Geometry: 10% =6 questions Students will further develop their understanding of characteristics of previously studied geometric figures. M3G1 Students will further develop their understanding of geometric figures by drawing them. They will also state and explain their properties. M3G1a Draw and classify previously learned fundamental geometric figures and scalene, isosceles, and equilateral triangles. There are three special names given to triangles that tell how many sides (or angles) are equal. Equilateral Triangle Three equal sides Three equal angles, always 60° Isosceles Triangle Two equal sides Two equal angles Scalene Triangle No equal sides No equal angles Triangles can also have names that tell you what type of angle is inside: Acute Triangle All angles are less than 90° Right Triangle Has a right angle (90°) Obtuse Triangle Has an angle more than 90° 22 M3G1b. Identify and compare the properties of fundamental geometric figures c. Examine and compare angles of fundamental geometric figures The Rectangle means "right angle" and show equal sides A rectangle is a four-sided shape where every angle is a right angle (90°). Also opposite sides are parallel and of equal length. The Rhombus A rhombus is a four-sided shape where all sides have equal length. Also opposite sides are parallel and opposite angles are equal. Another interesting thing is that the diagonals (dashed lines in second figure) of a rhombus bisect each other at right angles The Square means "right angle" show equal sides A square has equal sides and every angle is a right angle (90°). Also opposite sides are parallel. A square also fits the definition of a rectangle (all angles are 90°), and a rhombus (all sides are equal length). The Parallelogram Opposite sides are parallel and equal in length, and opposite angles are equal (angles "a" are the same, and angles "b" are the same) 23 The Trapezoid A trapezoid has one pair of opposite sides parallel. Acute Angles An acute angle is one which is less than 90° Right Angles A right angle is an internal angle which is equal to 90° Obtuse Angles An obtuse angle is one which is more than 90° but less than 180° Straight Angle A straight angle is 180 degrees 24 M3G1d. Identify the center, diameter, and radius of a circle A circle is easy to make: Draw a curve that is "radius" away from a central point. And so: All points are the same distance from the center. Radius and Diameter The Radius is the distance from the center to the edge. The Diameter starts at one side of the circle, goes through the center and ends on the other side. So the Diameter is twice the Radius: Diameter = 2 × Radius M3M3c. Determine the perimeter of a geometric figure by measuring and summing/adding the lengths of the sides. Perimeter The distance around a two-dimensional shape. Example: the perimeter of this rectangle is a+b+a+b = 2(a+b) The perimeter of a circle is called the circumference. See: Circumference 25 Algebra: 7% = 4 questions Students will understand how to express relationships as mathematical expressions. M3G1.Students will use mathematical expressions to represent relationships between quantities and interpret given expressions. a. Describe and extend numeric and geometric patterns. b. Describe and explain a quantitative relationship represented by a formula (such as perimeter of a geometric figure). c. Use a symbol, such as and ∆, to represent an unknown in a number sentence. 60 x = 120 = 2 60 x 2 = 120 Evaluate 5n when n=12 Step 1 Step 2 Step 3 Write the expression Replace n with 12 Solve 5n 5 x 12 5 x 12 = 60 Data Analysis and Probability: 5% = 3 questions Students will gather, organize, and display data and interpret graphs. M3D1.Students will gather, organize and display data and interpret graphs. a. Solve problems by organizing and displaying data in charts, tables and graphs. b. Construct and interpret line plot graphs, pictographs, Venn diagrams, and bar graphs using scale increments of 1,2,5 and 10. Graph Line plot Line graph Bar graph Pictograph Circle graph Venn diagram defined A diagram that organizes data using a number line. A graph that uses lines to show changes in data over time. A graph in which information is shown by means of rectangular bars. A graph in which information is shown by means of pictures or symbols. A graph that represents data as part of a circle. Two or more overlapping circles that show the relationship between sets(similarity/differences). 26 Line Plot Suppose thirty people live in an apartment building. These are the following ages: 58, 30, 37, 36, 34, 49, 35, 40, 47, 47, 39, 54, 47, 48, 54, 50, 35, 40, 38, 47, 48, 34, 40, 46, 49, 47, 35, 48, 47, 46 Your first step should be: placing the values in numerical order. 30, 34, 34, 35, 35, 35, 36, 37, 38, 39, 40, 40, 40, 46, 46, 47, 47, 47, 47, 47, 47, 48, 48, 48, 49, 49, 50, 54, 54, 58 Now create your graph. This graph shows all the ages of the people who live in the apartment building. It shows the youngest person is 30, and the oldest is 58. Most people in the building are over 46 years of age. The most common age is 47. Line plots allow several features of the data to become more obvious. For example, outliers, clusters, and gaps are apparent. Outliers are data points whose values are significantly larger or smaller than other values, such as the ages of 30, and 58. Clusters are isolated groups of points, such as the ages of 46 through 50. Gaps are large spaces between points, such as 41 and 45. 27 Line Graphs A line graph is a way to summarize how two pieces of information are related and how they vary depending on one another. The numbers along a side of the line graph are called the scale. Example 1: The graph above shows how John's weight varied from the beginning of 1991 to the beginning of 1995. The weight scale runs vertically, while the time scale is on the horizontal axis. Following the gridlines up from the beginning of the years, we see that John's weight was 68 kg in 1991, 70 kg in 1992, 74 kg in 1993, 74 kg in 1994, and 73 kg in 1995. Examining the graph also tells us that John's weight increased during 1991 and 1995, stayed the same during 1991, and fell during 1994. Pictograph 10 students chose cat as their favorite pet 4 students chose dog as their favorite pet 6 students chose hamster as their favorite pet 28 Bar Graph The bar chart below shows the weight in kilograms of some fruit sold one day by a local market. We can see that 52 kg of apples were sold, 40 kg of oranges were sold, and 8 kg of star fruit were sold. Circle Graph The circle graph below shows the ingredients used to make a sausage and mushroom pizza. The fraction of each ingredient by weight shown in the pie chart below is now given as a percent. Again, we see that half of the pizza's weight, 50%, comes from the crust. Note that the sum of the percent sizes of each slice is equal to 100%. Graphically, the same information is given, but the data labels are different. Always be aware of how any chart or graph is labeled. 29 Venn Diagram An example of a three-part Venn diagram follows: 30 References (websites) Math Worksheet Center AA Math Math Is Fun Houghton Mifflin Math Math Slice Learning NC Jennifer Nord Revise Soft Homeschool Math Model Method Jamit 31