Subtract 27/12 from 42/54, Solve 42/54

Subtract 27/12 from 42/54

1^st number: 42/54, 2^nd number: 2 3/12

42/54 - 27/12 is -53/36.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 12 is 108

Next, find the equivalent fraction of both fractional numbers with denominator 108
For the 1st fraction, since 54 × 2 = 108,
42/54 = 42 × 2/54 × 2 = 84/108
Likewise, for the 2nd fraction, since 12 × 9 = 108,
27/12 = 27 × 9/12 × 9 = 243/108
Subtract the two like fractions:
84/108 - 243/108 = 84 - 243/108 = -159/108
After reducing the fraction, the answer is -53/36

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