Subtract 21/56 from 7/15, Solve 7/15

Subtract 21/56 from 7/15

7/15 - 21/56 is 11/120.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 56 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 15 × 56 = 840,
7/15 = 7 × 56/15 × 56 = 392/840
Likewise, for the 2nd fraction, since 56 × 15 = 840,
21/56 = 21 × 15/56 × 15 = 315/840
Subtract the two like fractions:
392/840 - 315/840 = 392 - 315/840 = 77/840
After reducing the fraction, the answer is 11/120

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