Subtract 63/16 from 21/28, Solve 21/28

Subtract 63/16 from 21/28

1^st number: 21/28, 2^nd number: 3 15/16

21/28 - 63/16 is -51/16.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 16 is 112

Next, find the equivalent fraction of both fractional numbers with denominator 112
For the 1st fraction, since 28 × 4 = 112,
21/28 = 21 × 4/28 × 4 = 84/112
Likewise, for the 2nd fraction, since 16 × 7 = 112,
63/16 = 63 × 7/16 × 7 = 441/112
Subtract the two like fractions:
84/112 - 441/112 = 84 - 441/112 = -357/112
After reducing the fraction, the answer is -51/16

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