Subtract 15/24 from 21/56, Solve 21/56

Subtract 15/24 from 21/56

21/56 - 15/24 is -1/4.

Find the least common denominator or LCM of the two denominators:
LCM of 56 and 24 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 56 × 3 = 168,
21/56 = 21 × 3/56 × 3 = 63/168
Likewise, for the 2nd fraction, since 24 × 7 = 168,
15/24 = 15 × 7/24 × 7 = 105/168
Subtract the two like fractions:
63/168 - 105/168 = 63 - 105/168 = -42/168
After reducing the fraction, the answer is -1/4

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