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Page 101
Decimals and Percents
U.S. Traditional Long Division: Decimal Divisors
To use U.S. traditional long division to divide by a decimal
number, such as 0.7 or 4.5, you can find an equivalent
problem that has no decimal in the divisor. The answer to
the equivalent problem is the same as the answer to your
original problem.
Step 1: Think of the division problem as a fraction.
Step 2: Use the multiplication rule to find an equivalent
fraction that has no decimal in the denominator.
Step 3: Think of the equivalent fraction as a division problem.
Step 4: Solve the division problem. The answer to the
equivalent problem is the same as the answer to the
original problem.
364 / 0.8 ?
Step 1: Think of the division problem as a fraction.
364
364 / 0.8 0.8
Step 2: Find an equivalent fraction with no decimal in the denominator.
364 10
0.8 10
3640
8
Step 3: Think of the equivalent fraction as a division problem.
3640
8
3640 / 8
Step 4: Solve the equivalent division problem.
455
83
6
4
0
32
44
40
40
40
0
3640
364
Because 8 and 0.8 are equivalent fractions, the division problems 3640 / 8 and 364 / 0.8
are equivalent. So the answer to 3640 / 8 is the same as the answer to 364 / 0.8.
364 / 0.8 455
54G
EM3SRB_G5_54A-54J.qxd
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Page 102
Decimals and Percents
U.S. Traditional Long Division:
Decimal Divisors and Dividends
Sometimes both the divisor (the number you are dividing by) and the dividend
(the number being divided) are decimal numbers. To use U.S. traditional long
division in such cases, you can find an equivalent problem that has no decimal
in the divisor. (Having a decimal part in the dividend is okay.) The answer
to the equivalent problem is the same as the answer to your original problem.
2.76 / 0.4 ?
Step 1: Think of the division problem as a fraction.
2.76
2.76 / 0.4 0.4
Step 2: Find an equivalent fraction with no decimal in the denominator.
2.76 * 10
0.4 * 10
27.6
4
Step 3: Think of the equivalent fraction as a division problem.
27.6
4
27.6 / 4
Step 4: Solve the division problem.
6.9
42
7
.6
24
36
3 6
0
27.6
2.76
Because 4 and 0.4 are equivalent fractions, the division problems
27.6 / 4 and 2.76 / 0.4 are equivalent. So the answer to 27.6 / 4 is the same
as the answer to 2.76 / 0.4.
2.76 / 0.4 6.9
Divide.
1. 687 / 0.3 = ?
2. 29.6 /1.8 = ?
3. 3.95 / 0.05 = ?
Check your answers on page 442.
54H
4. 16.17 / 0.7 = ?