&&66 8VHSDUHQWKHVHVEUDFNHWVRUEUDFHVLQQXPHULFDOH[SUHVVLRQV NS 2.1*2$ Add, subtract, multiply, and divide with decimals; add with DQGHYDOXDWHH[SUHVVLRQVZLWKWKHVHV\PEROV UNDERLYING SKILLS AND CONCEPTS: negative integers; subtract positive integers from negative integers; and verify the reasonableness of the results. computation with whole numbers computation with integers Order of Operations Mathematicians use parentheses to show what operations to do first. Step 1: Do all operations in Parentheses. P. E. M. D. A. S. (2 " 5) & (3 " 4) ! 22 $ ? 10 & 12 ! 4 $ ? 22 ! 4 $ 18 Step 2: Evaluate Exponents. Step 3: Do Multiplication and Division in order from left to right. Step 4: Do Addition and Subtraction in order from left to right. 1 Was the expression evaluated using order of operations? 17 ! 5 " 9 # 3 $ 36 Hint: No exponents, no parentheses. So, go to Step 3: 17 ! 45 # 3 =? 36 3 Place parentheses to show the order of operations used to get 36. (17 ! 5) " (9 # 3) $ 36 page 102 Place parentheses to show correct order of operations. x $ !5 & 3 " 42 & 81 # 9 Step 1: Evaluate exponents Step 2: Do multiplication and division. 17 ! 42 # 4 % 36 No. Order of operations was not used. 17 ! 5 " 9 # 3 $ 36 2 !5 & 3 " (42) & 81 # 9 17 ! 15 # 4 =? 36 E x am p l E E x am p l E !5 & (3 " (42)) & (81 # 9) Step 3: Do addition and subtraction last. (4 " 3) & (7 " 2) ! 42 $ n Parentheses Exponents Multiplication Division Addition Subtraction Chapter 9 – Lesson 3 E – © CSL Associates, Inc. All rights reserved. E x am p l E Name P RAC T I C E Evaluate each expression. Use order of operations. Show each step. 1. 24 3 8 2. 125 5 5 10 24 24 0 25 5 10 20 10 30 3. (16 12) 12 4 (12) 4. 27 33 0 5 (4) 12 4 (12) 48 27 27 0 5 4 (12) 27 27 0 12 24 12 00 0 A B C D (16 4) (12 3) (16 4) 12 3 Do parentheses. Then divide before subtracting. (5 5) 9 3 (10 9) 3 ? So, 10 3 1 3 72 40 10 72 (40 10) 7 1 3 3 5 4 3 3 (5 4) 3 Math Reasoning Order of Operations MR 2.2 6. Write an equation that will let you find the area of the figure. Use parentheses and exponents where you can. Then solve. A 52 (8 4) (8 6) 2 A 25 32 (48 2) 3 in. A 57 24 A 81 sq in. 8 in. 5 in. A 25 32 24 5 in. E – © CSL Associates, Inc. All rights reserved. Choose the best answer. Explain how you decided. 5. Which equation is NOT true? 4 in. Chapter 9 – Lesson 3 6 in. page 103 MCX94.HW.CL.G5.FM&Lesson.v211 8/2/04 18:02 Page 70 Name …at home! P RAC T I C E Evaluate each expression. Use order of operations. Show each step. 1. 25 3 6 2. 145 5 5 10 25 18 29 5 10 7 29 5 34 3. (18 12) 12 4 (12) 4. 8 23 0 2 (6) 12 4 (12) 72 4 (12) 00 12 30 0 18 Choose the best answer. Explain how you decided. 5. Which equation is NOT true? A B C D (16 4) (9 3) (16 4) 9 3 Do parentheses. Then divide before subtracting. (4 4) 6 3 (8 6) 3 ? So, 8 2 2 3 72 30 10 72 (30 10) 6 2 3 3 6 4 3 3 (6 4) 3 Math Reasoning Order of Operations MR 2.2 6. Write an equation that will let you find the area of the figure. Use parentheses and exponents where you can. Then solve. 1 (52) (8 4) 1 (8 6) A 2 2 1 (5 5) (8 4) 1 (8 6) A 3 in. 2 2 25 32 48 A 5 in. 8 in. 2 5 in. page 70 4 in. 2 73 A 32 2 6 in. 1 sq in. A 68 2 Home Resource and Homework Chapter 9 Lesson 3 E – © CSL Associates, Inc. All rights reserved. 8 8 0 2 MCX94TEG5CH01_32.v7.4.2 2/24/01 19:44 Page 191 Name P RAC T I C E Evaluate each expression. Use order of operations. Show each step. 1. 24 3 8 2. 125 5 5 10 24 24 0 25 5 10 20 10 30 3. (16 12) 12 4 (12) 4. 27 33 0 5 (4) 12 4 (12) 48 27 27 0 5 4 (12) 27 27 0 12 24 12 00 0 A B C D (16 4) (12 3) (16 4) 12 3 Do parentheses. Then divide before subtracting. (5 5) 9 3 (10 9) 3 ? So, 10 3 1 3 72 40 10 72 (40 10) 7 1 3 3 5 4 3 3 (5 4) 3 Math Reasoning Order of Operations MR 2.2 6. Write an equation that will let you find the area of the figure. Use parentheses and exponents where you can. Then solve. A 52 (8 4) (8 6) 2 A 25 32 (48 2) 3 in. A 57 24 A 81 sq in. 8 in. 5 in. A 25 32 24 5 in. E – © CSL Associates, Inc. All rights reserved. Choose the best answer. Explain how you decided. 5. Which equation is NOT true? 4 in. Chapter 9 – Lesson 3 6 in. Student Book Page page 103 Name …at home! P RAC T I C E Evaluate each expression. Use order of operations. Show each step. 1. 25 3 6 2. 145 5 5 10 25 18 29 5 10 7 29 5 34 3. (18 12) 12 4 (12) 4. 8 23 0 2 (6) 12 4 (12) 72 4 (12) 00 12 30 0 18 Choose the best answer. Explain how you decided. 5. Which equation is NOT true? A B C D (16 4) (9 3) (16 4) 9 3 Do parentheses. Then divide before subtracting. (4 4) 6 3 (8 6) 3 ? So, 8 2 2 3 72 30 10 72 (30 10) 6 2 3 3 6 4 3 3 (6 4) 3 Math Reasoning Order of Operations MR 2.2 6. Write an equation that will let you find the area of the figure. Use parentheses and exponents where you can. Then solve. 3 in. 1 1 A (5 5) (8 4) (8 6) 2 2 8 in. 48 25 A 32 2 2 5 in. 5 in. page 70 1 1 A (52) (8 4) (8 6) 2 2 4 in. 73 A 32 2 6 in. 1 A 68 sq in. 2 Home Resource and Homework Chapter 9 Lesson 3 E – © CSL Associates, Inc. All rights reserved. 8 8 0 2