Subtract 15/32 from 21/56, Solve 21/56

Subtract 15/32 from 21/56

21/56 - 15/32 is -3/32.

Find the least common denominator or LCM of the two denominators:
LCM of 56 and 32 is 224

Next, find the equivalent fraction of both fractional numbers with denominator 224
For the 1st fraction, since 56 × 4 = 224,
21/56 = 21 × 4/56 × 4 = 84/224
Likewise, for the 2nd fraction, since 32 × 7 = 224,
15/32 = 15 × 7/32 × 7 = 105/224
Subtract the two like fractions:
84/224 - 105/224 = 84 - 105/224 = -21/224
After reducing the fraction, the answer is -3/32

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