o M s 5 t Challenging 1 s ’ o i h O g n i r e Skills Mast Ohio 6 Mathematics o M s 5 t Challenging 1 s ’ o i h O g n i r e Skills Mast Ohio Master Ohio’s 15 most challenging mathematics skills with SkillBridge. With lesson topics chosen based on actual state test data, SkillBridge offers help in the skills that truly are the most troublesome. As students move through each lesson, they are equipped with guidance and connections that allow them to show independent skill mastery by the end of the lesson. Ohio references in each lesson offer a unique and familiar point of entry into difficult skills. Mathema tics Ohio’s 15 most challenging skills in mathematics, grade 6 • Associative Property • Input-Output Tables • Multiples • Identifying Triangles • Factors • Area • Multiplying and Dividing Fractions • Volume • Fractions and Percents • Circle Graphs • Ratios • Proportions • Range • Probability • Evaluating Expressions Daniel Carter Beard Bridge in Cincinnati, Ohio Catalog Number OHB2064W1 P.O. Box 2180 Iowa City, Iowa 52244-2180 ISBN 978-0-7836-6274-9 50599 STUDENT NAME PHONE: 800-776-3454 FAX: 877-365-0111 www.BuckleDown.com 1BROH06MM01.indd 1-2 9 780783 662749 11/25/08 1:48:54 PM Table of Contents Associative Property (PA.D.3)................................................... 4 Multiples (NO.G.2b). .................................................................... 8 Factors (NO.G.2a)...................................................................... 12 Multiplying and Dividing Fractions (NO.H.11, NO.H.12).............. 16 Fractions and Percents (NO.D.5). ........................................... 20 Ratios (NO.D.5)......................................................................... 24 Proportions (NO.D.14)............................................................... 28 Evaluating Expressions (PA.G.6)............................................ 32 Input-Output Tables (PA.B.1)................................................... 36 Identifying Triangles (GS.D.3). ................................................ 40 Area (ME.C.3b)........................................................................... 44 OH6 © 2009 Buckle Down – Options Publishing. COPYING IS FORBIDDEN BY LAW. Volume (ME.C.3a)...................................................................... 48 Range (DP.F.4). ......................................................................... 52 Circle Graphs (DP.A.1). ............................................................ 56 Probability (DP.K.7).................................................................. 60 PA.D.3 OH At the beginning of each lesson, you will see a box with the shape of Ohio and an Academic Content Standard code in it. This code tells you what is being covered in the lesson. 3 1BROH06MM_FM.indd 3 11/13/08 1:42:07 PM PA.D.3 OH Associative Property The associative property is a rule about the way numbers are grouped. The associative property states that the sum or product of a set of numbers is the same even when the grouping is changed. According to the order of operations, when you solve an expression, you must complete any operations inside parentheses first. The associative property proves that moving the parentheses to change the grouping of the numbers when you are adding or multiplying will not change the answer. The Rock and Roll Hall of Fame Museum is located in Cleveland, close to the shore of Lake Erie. (a b) c 5 a (b c) (a 3 b) 3 c 5 a 3 (b 3 c) The associative property of addition states that the grouping of addends can change and the sum will be the same. Example 1 (18 12) 15 5 18 (12 ) For the equation to be equal, the same addends must be on each side of the equal sign. The number 15 is missing on the right side of the equation. Check the answer by finding the sum of each side. Add the numbers in parentheses first, to follow the order of operations. (18 12) 15 5 18 (12 15) 30 15 5 18 27 455 45 The missing number is 15. The associative property of addition shows that you can group the addends in any order and the sum is the same. Write the missing number. 20 (26 23) 5 (20 ) 23 OH6 © 2009 Buckle Down – Options Publishing. COPYING IS FORBIDDEN BY LAW. Build A Bridge 1 Write the missing number. 4 6M_Associative Property.indd 4 11/13/08 1:47:18 PM The associative property of multiplication states that if the grouping of factors is changed, the product will be the same. Example 2 Use the associative property of multiplication to find the equivalent expression. Build A Bridge 2 A (7 1 10) 1 4 Use the associative property of multiplication to find the equivalent expression. B 7 • (10 • 7) 34 • (42 • 26) 5 C 7 • (10 1 4) A (34 42) 26 D 7 • (10 • 4) B 34 • (26 • 40) (7 • 10) • 4 5 Check each answer choice to see if the same three factors are being used. Then, check for the same operation signs. Finally, compare the way the factors are grouped. C (34 • 42) • 26 D (34 • 42) 26 Choice D: 7 • (10 • 4) is the equivalent expression. So, (7 • 10) • 4 5 7 • (10 • 4). OH6 © 2009 Buckle Down – Options Publishing. COPYING IS FORBIDDEN BY LAW. Example 3 Which equation shows the associative property of addition? A (8 1 6) 2 9 5 8 2 (6 1 9) B 8 1 (6 1 9) 5 (8 1 6) 1 9 C 8(6 1 9) 5 8(6) 1 8(9) D (8 • 6) • 9 5 8 • (6 • 9) You are looking for the associative property of addition, so look for addition signs. Check each answer choice to see if the same addends are being used. Finally, compare the way the numbers are grouped. Choice B demonstrates the associative property of addition: 8 1 (6 1 9) 5 (8 1 6) 1 9. Build A Bridge 3 The associative property only works for addition and multiplication. Consider (12 2 5) 2 3 and 12 2 (5 2 3). The numbers are the same, but the two expressions are not equivalent. The property does not work for 24 4 (6 4 3) and (24 4 6) 4 3 either. They are also not equivalent. Subtraction and division are not associative. 5 6M_Associative Property.indd 5 11/13/08 1:47:21 PM Guided PractiCE 1 Define the associative property. 2 Explain how to use the associative property of multiplication to write an equivalent expression to 10 • (4 • 8). 3 Does the associative property work for subtraction? Give an example. For Numbers 4–7, use the associative property to write the missing number. 6 26 • ( 19) 5 • (37 • 54) 5 (48 • 37) • 54 • 60) 5 (26 • 35) • 60 7 (81 18) 5 81 (18 71) For Numbers 8–10, use the associative property to find the equivalent expression. 8 (15 • 29) • 52 5 A 15 • (29 • 15) B 15 • (29 • 52) C 15 (29 52) D 15 (29 • 52) 9 3.8 (4.1 2.4) 5 A (3.8 4.1) 2.4 B 3.8 • (4.1 2.4) C (3.8 4.1) • 2.4 D 3.8 • (4.1 • 2.4) 10 172 • (86 • 93) 5 A 172 (86 • 93) B (172 • 86) • 86 C (172 • 86) • 93 D (172 86) 86 OH6 © 2009 Buckle Down – Options Publishing. COPYING IS FORBIDDEN BY LAW. 4 (13 11) 19 5 13 ( 6 6M_Associative Property.indd 6 11/13/08 1:47:21 PM Practice For Numbers 1–4, use the associative property to write the missing number. 1 (42 • ) • 26 5 42 • (34 • 26) 3 (8.3 1 7.5) 1 9.4 5 2 (98 1 85) 1 5 98 1 (85 1 76) 1 (7.5 + 9.4) 4 36 • (62 • 21) 5 (36 • 62) • For Numbers 5–7, use the associative property to find the equivalent expression. 5 12.8 1 (15.2 1 17.1) 5 A 12.8 • (15.2 1 17.1) B (15.2 1 15.2) 1 17.1 C (12.8 1 15.2) 1 17.1 D 12.8 • (15.2 • 17.1) A (391 1 425) 1 391 B 391 1 (260 1 425) C 391 1 (260 • 425) D 391 • (260 • 425) A 63 1 (39 • 69) B (63 • 39) • 96 C 63 • (39 • 69) D 63 1 (39 • 69) 6 (391 1 260) 1 425 5 OH6 © 2009 Buckle Down – Options Publishing. COPYING IS FORBIDDEN BY LAW. 7 (63 • 39) • 69 5 For Numbers 8–10, circle T for true or F for false for each equation. 8 T F (20 1 28) 1 24 5 20 1 (28 • 24) 9 T F (5.1 • 3.6) • 7.2 5 (3.6 • 3.6) • 7.2 10 T F 109 1 (213 1 391) 5 (109 1 213) 1 391 11 Six groups of visitors toured the Rock and Roll Hall of Fame Museum. Each group had 8 visitors. Every visitor received 2 postcards on the tour. Which expression shows the total number of postcards given out during the tours? A 6 • (8 • 2) 5 (6 • 8) • 2 C (6 1 8) 1 2 5 6 • (8 • 2) B (6 1 8) 1 2 5 6 1 (8 1 2) D 6 • (8 4 2) 5 (6 • 8) 4 2 7 6M_Associative Property.indd 7 11/26/08 11:14:24 AM