Page 86 - Basic College Mathematics with Early Integers

S E C T ION 1. 7 I DIVIDING WHOLE NUMBERS 63

Example 4 Divide: 3705 , 5. Check by multiplying. PRACTICE 4
Divide. Check by multiplying.
Solution: a. 4908 , 6
7 37÷5=7 with 2 left. Place this estimate, 7, over the 7 in 37. b. 2212 , 4
53705 c. 753 , 3
–35 7(5)=35
20 37-35=2, and 2 is less than the divisor 5.
Bring down the 0.
74 20÷5=4
53705
–35
20
– 20 4(5)=20
05 20-20=0, and 0 is less than the divisor 5.
Bring down the 5.
741 5 , 5 = 1
53705
– 35
20
– 20

5
– 5 1(5) = 5
0 5 - 5 = 0
Check:
741 Since division
* 5 and multiplication are reverse
operations, don’t forget that
3705
a division problem can be
checked by multiplying.
Work Practice 4

Example 5 Divide and check: 1872 , 9 PRACTICE 5
Divide and check by
Solution: multiplying.

208 a. 72128
91872
b. 945,900
– 18 2(9) = 18
07 18 - 18 = 0; bring down the 7.
– 0 0(9) = 0
72 7 - 0 = 7; bring down the 2.
– 72 8(9) = 72
0 72 - 72 = 0
#
Check: 208 9 = 1872
Work Practice 5

Answers
4. a. 818 b. 553 c. 251
5. a. 304 b. 5100