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3-6 Dividing Decimals by Whole Numbers
Warm Up
Problem of the Day
Lesson Presentation
Course 1
3-6 Dividing Decimals by Whole Numbers
Warm Up
Divide.
1. 56,000 ÷ 8
7,000
2. 5,219 ÷ 17
307
3. 9,180 ÷ 12
765
Course 1
3-6 Dividing Decimals by Whole Numbers
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
Course 1
3-6 Dividing Decimals by Whole Numbers
Learn to divide decimals by whole
numbers.
Course 1
3-6 Dividing Decimals by Whole Numbers
Remember!
Quotient
0.15
5 0.75
Divisor
Course 1
Dividend
3-6 Dividing Decimals by Whole Numbers
Additional Example 1A: Dividing a Decimal by a
Whole Number
Find the quotient.
0.84 ÷ 3
0.28
3 0.84
–6
24
– 24
0
Course 1
Place a decimal point in the quotient
directly above the decimal point in
the dividend. Divide as you would
with whole numbers.
3-6 Dividing Decimals by Whole Numbers
Additional Example 1B: Dividing a Decimal by a
Whole Number
Find the quotient.
3.56 ÷ 4
0. 89
4 3.56
– 32
36
– 36
0
Course 1
Place a decimal point in the quotient
directly above the decimal point in
the dividend. Divide as you would
with whole numbers.
3-6 Dividing Decimals by Whole Numbers
Check It Out: Example 1A
Find the quotient.
0.72 ÷ 3
0.24
3 0.72
–6
12
– 12
0
Course 1
Place a decimal point in the quotient
directly above the decimal point in
the dividend. Divide as you would
with whole numbers.
3-6 Dividing Decimals by Whole Numbers
Check It Out: Example 1B
Find the quotient.
2.96 ÷ 4
0. 74
4 2.96
– 28
16
– 16
0
Course 1
Place a decimal point in the quotient
directly above the decimal point in
the dividend. Divide as you would
with whole numbers.
3-6 Dividing Decimals by Whole Numbers
Additional Example 2A: Evaluating Decimal
Expressions
Evaluate 0.936 ÷ x for the given value of x.
x=9
0.936 ÷ x
0.936 ÷ 9
0.104
9 0.936
–9
3
–0
36
– 36
0
Course 1
Substitute 9 for x.
Sometimes you need to use a
zero as a placeholder.
9 > 3, so place a zero in the
quotient and divide 9 into 36.
3-6 Dividing Decimals by Whole Numbers
Additional Example 2B: Evaluating Decimal
Expressions
Evaluate 0.936 ÷ x for the given value of x.
x = 18
0.936 ÷ x
0.936 ÷ 18
0.052
18 0.936
–0
93
– 90
36
– 36
0
Course 1
Substitute 18 for x.
Sometimes you need to use a
zero as a placeholder.
18 > 9, so place a zero in the
quotient and divide 18 into 93.
3-6 Dividing Decimals by Whole Numbers
Check It Out: Example 2A
Evaluate 0.636 ÷ x for the given value of x.
x=6
0.636 ÷ x
0.636 ÷ 6
0.106
6 0.636
–6
3
–0
36
– 36
0
Course 1
Substitute 6 for x.
Sometimes you need to use a
zero as a placeholder.
6 > 3, so place a zero in the
quotient and divide 6 into 36.
3-6 Dividing Decimals by Whole Numbers
Check It Out: Example 2B
Evaluate 0.636 ÷ x for the given value of x.
x = 12
0.636 ÷ x
0.636 ÷ 12
0.053
12 0.636
–0
63
– 60
36
– 36
0
Course 1
Substitute 12 for x.
Sometimes you need to use a
zero as a placeholder.
12 > 6, so place a zero in the
quotient and divide 12 into 63.
3-6 Dividing Decimals by Whole Numbers
Remember!
Multiplication can “undo” division. To check your
answer to a division problem, multiply the divisor
by the quotient.
Course 1
3-6 Dividing Decimals by Whole Numbers
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. 53 Place a decimal point in the quotient
4 $10.12 directly above the decimal point in
–8
the dividend. Divide as you would
with whole numbers.
21
– 20
Check
12
2.53  4 = 10.12
– 12
Each person should pay $2.53.
0
Course 1
3-6 Dividing Decimals by Whole Numbers
Check It Out: Example 3
Ty and three of his friends are building a fence.
The lumber cost $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.
$5.36
4 $21.44
– 20
14
– 12
24
– 24
0
Course 1
Place a decimal point in the quotient
directly above the decimal point in
the dividend. Divide as you would
with whole numbers.
Check
5.36  4 = 21.44
Each person should pay $5.36.
Decimals
by Whole
3-6 Dividing
Insert Lesson
Title
HereNumbers
Lesson Quiz
Find each quotient.
1. 3.12 ÷ 8
0.39
2. 5.68 ÷ 8
0.71
Evaluate the expression 1.25 ÷ x for the given
value of x.
3. x = 5 0.25
4. x = 25 0.05
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? $18.25
Course 1