Unit 5 Dividing Whole Numbers
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Example 5-4
106
9
|
––––
957
– 9
‾
05
– 0
‾
57
– 54
‾
3
r3
Checking Division
Division can be thought of as the inverse of multiplication. Because of this, division
problems can be checked by multiplication. Once a division problem has been
calculated, it can be checked by multiplying the quotient by the divisor. If there was
a remainder in the answer, it is then added to the answer. For example, the division
problem 76 ÷ 6 is checked with multiplication.
12
× 6
‾
72
+ 4
‾
76
1
12
6
|
–––
76
– 6
‾
16
– 12
‾
4
r4
Division can also be used to check the accuracy of a multiplication problem.
48 ÷ 6 = 8 or 48 ÷ 8 = 6
Dividing Denominate Numbers
When dividing a denominate number by a whole number, the denominate number’s
unit of measure is applied to the fi nal answer.
12 yd ÷ 3 = 4 yd
18′ ÷ 6 = 3′
When dividing two denominate numbers containing a squared dividend, the
divisor’s unit of measure will cancel out the part of the dividend’s unit they have in
common, resulting in the answer containing a single unit of measure.
81 sq ft
_______
9′
= 9′