1. Learn to divide decimals by whole numbers.

2. Remember!
Quotient
0.15 5
0.75
Divisor
Dividend

3. 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

4. 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

5. 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

6. 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

7. Additional Example 2A: Evaluating Decimal Expressions
Evaluate ÷ 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
9 > 3, so place a zero in the quotient and divide 9 into 36. 3
– 0 36
– 36

8. Additional Example 2B: Evaluating Decimal Expressions
Evaluate ÷ 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.
– 0
18 > 9, so place a zero in the quotient and divide 18 into 93. 93
– 90 36
– 36

9. Check It Out: Example 2A
Evaluate ÷ 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
6 > 3, so place a zero in the quotient and divide 6 into 36. 3
– 0 36
– 36

10. Check It Out: Example 2B
Evaluate ÷ 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.
– 0
12 > 6, so place a zero in the quotient and divide 12 into 63. 63
– 60 36
– 36

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

12. Additional Example 3: Consumer Application Jodi and three of her friends are making a tile design. The materials cost $ 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.

13. Check It Out: Example 3
Ty and three of his friends are building a fence. The lumber costs $ 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.