Subtract 15/16 from 21/56, Solve 21/56

Subtract 15/16 from 21/56

21/56 - 15/16 is -9/16.

Find the least common denominator or LCM of the two denominators:
LCM of 56 and 16 is 112

Next, find the equivalent fraction of both fractional numbers with denominator 112
For the 1st fraction, since 56 × 2 = 112,
21/56 = 21 × 2/56 × 2 = 42/112
Likewise, for the 2nd fraction, since 16 × 7 = 112,
15/16 = 15 × 7/16 × 7 = 105/112
Subtract the two like fractions:
42/112 - 105/112 = 42 - 105/112 = -63/112
After reducing the fraction, the answer is -9/16

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