Warm Up Problem of the Day Lesson Presentation Lesson Quizzes

Warm Up Divide. 1. 56,000 ÷ 8 2. 5,219 ÷ 17 3. 9,180 ÷ 12 7,000 307 765

In his pocket, Bill has $0.77 made up of 10 coins. What are the coins? Problem of the Day In his pocket, Bill has $0.77 made up of 10 coins. What are the coins? 1 quarter, 3 dimes, 4 nickels, and 2 pennies

Learn to divide decimals by whole numbers.

Remember! Quotient 0.15 5 0.75 Divisor Dividend

Additional Example 1A: Dividing a Decimal by a Whole Number Find the quotient. 0.84 ÷ 3 0. 2 8 Place a decimal point in the quotient directly above the decimal point in the dividend. Divide as you would with whole numbers. 3 0.84 – 6 24 – 24

Additional Example 1B: Dividing a Decimal by a Whole Number Find the quotient. 3.56 ÷ 4 0. 8 9 Place a decimal point in the quotient directly above the decimal point in the dividend. Divide as you would with whole numbers. 4 3.56 – 32 36 – 36

Check It Out: Example 1A Find the quotient. 0.72 ÷ 3 0. 2 4 Place a decimal point in the quotient directly above the decimal point in the dividend. Divide as you would with whole numbers. 3 0.72 – 6 12 – 12

Check It Out: Example 1B Find the quotient. 2.96 ÷ 4 0. 7 4 Place a decimal point in the quotient directly above the decimal point in the dividend. Divide as you would with whole numbers. 4 2.96 – 28 16 – 16

Additional Example 2A: Evaluating Decimal Expressions Evaluate 0.936 ÷ x for the given value of x. x = 9 0.936 ÷ x 0.936 ÷ 9 Substitute 9 for x. 0. 1 4 Sometimes you need to use a zero as a placeholder. 9 0.936 – 9 9 > 3, so place a zero in the quotient and divide 9 into 36. 3 – 0 36 – 36

Additional Example 2B: Evaluating Decimal Expressions Evaluate 0.936 ÷ x for the given value of x. x = 18 0.936 ÷ x 0.936 ÷ 18 Substitute 18 for x. 0. 5 2 Sometimes you need to use a zero as a placeholder. 18 0.936 – 0 18 > 9, so place a zero in the quotient and divide 18 into 93. 93 – 90 36 – 36

Check It Out: Example 2A Evaluate 0.636 ÷ x for the given value of x. x = 6 0.636 ÷ x 0.636 ÷ 6 Substitute 6 for x. 0. 1 6 Sometimes you need to use a zero as a placeholder. 6 0.636 – 6 6 > 3, so place a zero in the quotient and divide 6 into 36. 3 – 0 36 – 36

Check It Out: Example 2B Evaluate 0.636 ÷ x for the given value of x. x = 12 0.636 ÷ x 0.636 ÷ 12 Substitute 12 for x. 0. 5 3 Sometimes you need to use a zero as a placeholder. 12 0.636 – 0 12 > 6, so place a zero in the quotient and divide 12 into 63. 63 – 60 36 – 36

Multiplication can “undo” division Multiplication can “undo” division. To check your answer to a division problem, multiply the divisor by the quotient. Remember!

Additional Example 3: Consumer Application Jodi and three of her friends are making a tile design. The materials cost $10.12. If they share the cost equally, how much should each person pay? $10.12 should be divided into four equal groups. Divide $10.12 by 4. $2. 5 3 Place a decimal point in the quotient directly above the decimal point in the dividend. Divide as you would with whole numbers. 4 $10.12 – 8 21 – 20 Check 12 2.53  4 = 10.12 – 12 Each person should pay $2.53.

Check It Out: Example 3 Ty and three of his friends are building a fence. The lumber costs $21.44. If they share the cost equally, how much should each person pay? $21.44 should be divided into four equal groups. Divide $21.44 by 4. $5. 3 6 Place a decimal point in the quotient directly above the decimal point in the dividend. Divide as you would with whole numbers. 4 $21.44 – 20 14 – 12 Check 24 5.36  4 = 21.44 – 24 Each person should pay $5.36.

Lesson Quizzes Standard Lesson Quiz Lesson Quiz for Student Response Systems

Lesson Quiz Find each quotient. 1. 3.12 ÷ 8 2. 5.68 ÷ 8 Evaluate the expression 1.25 ÷ x for the given value of x. 3. x = 5 4. x = 25 5. The tennis team is having 3 of their tennis rackets restrung. The total cost is $54.75. What is the average cost per racket? 0.39 0.71 0.25 0.05 $18.25

Lesson Quiz for Student Response Systems 1. Identify the quotient. 6.84  9 A. 0.84 B. 0.76 C. 0.62 D. 0.58

Lesson Quiz for Student Response Systems 2. Identify the quotient. 4.59  9 A. 0.51 B. 0.62 C. 0.73 D. 0.84

Lesson Quiz for Student Response Systems 3. Evaluate the expression 1.44  x for x = 12. A. 12 B. 1.2 C. 0.12 D. 0.012

Lesson Quiz for Student Response Systems 4. Evaluate the expression 0.24  x for x = 12. A. 0.4 B. 0.2 C. 0.04 D. 0.02

Lesson Quiz for Student Response Systems 5. At a fruit stand, 8 pounds of apples cost $2.80. Identify the average cost of apples per pound. A. $35.00 B. $3.50 C. $0.35 D. $0.03