Subtract 21/72 from 63/4, Solve 15 3/4

Subtract 21/72 from 63/4

1^st number: 15 3/4, 2^nd number: 21/72

63/4 - 21/72 is 371/24.

Find the least common denominator or LCM of the two denominators:
LCM of 4 and 72 is 72

Next, find the equivalent fraction of both fractional numbers with denominator 72
For the 1st fraction, since 4 × 18 = 72,
63/4 = 63 × 18/4 × 18 = 1134/72
Likewise, for the 2nd fraction, since 72 × 1 = 72,
21/72 = 21 × 1/72 × 1 = 21/72
Subtract the two like fractions:
1134/72 - 21/72 = 1134 - 21/72 = 1113/72
After reducing the fraction, the answer is 371/24
In mixed form: 1511/24

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