Subtract 42/56 from 21/8, Solve 2 5/8

Subtract 42/56 from 21/8

1^st number: 2 5/8, 2^nd number: 42/56

21/8 - 42/56 is 15/8.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 56 is 56

Next, find the equivalent fraction of both fractional numbers with denominator 56
For the 1st fraction, since 8 × 7 = 56,
21/8 = 21 × 7/8 × 7 = 147/56
Likewise, for the 2nd fraction, since 56 × 1 = 56,
42/56 = 42 × 1/56 × 1 = 42/56
Subtract the two like fractions:
147/56 - 42/56 = 147 - 42/56 = 105/56
After reducing the fraction, the answer is 15/8
In mixed form: 17/8

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