Subtract 28/27 from 42/56, Solve 42/56

Subtract 28/27 from 42/56

1^st number: 42/56, 2^nd number: 1 1/27

42/56 - 28/27 is -31/108.

Find the least common denominator or LCM of the two denominators:
LCM of 56 and 27 is 1512

Next, find the equivalent fraction of both fractional numbers with denominator 1512
For the 1st fraction, since 56 × 27 = 1512,
42/56 = 42 × 27/56 × 27 = 1134/1512
Likewise, for the 2nd fraction, since 27 × 56 = 1512,
28/27 = 28 × 56/27 × 56 = 1568/1512
Subtract the two like fractions:
1134/1512 - 1568/1512 = 1134 - 1568/1512 = -434/1512
After reducing the fraction, the answer is -31/108

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