Subtract 15/12 from 42/56, Solve 42/56

Subtract 15/12 from 42/56

1^st number: 42/56, 2^nd number: 1 3/12

42/56 - 15/12 is -1/2.

Find the least common denominator or LCM of the two denominators:
LCM of 56 and 12 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 56 × 3 = 168,
42/56 = 42 × 3/56 × 3 = 126/168
Likewise, for the 2nd fraction, since 12 × 14 = 168,
15/12 = 15 × 14/12 × 14 = 210/168
Subtract the two like fractions:
126/168 - 210/168 = 126 - 210/168 = -84/168
After reducing the fraction, the answer is -1/2

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