Subtract 48/36 from 21/54, Solve 21/54

Subtract 48/36 from 21/54

1^st number: 21/54, 2^nd number: 1 12/36

21/54 - 48/36 is -17/18.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 36 is 108

Next, find the equivalent fraction of both fractional numbers with denominator 108
For the 1st fraction, since 54 × 2 = 108,
21/54 = 21 × 2/54 × 2 = 42/108
Likewise, for the 2nd fraction, since 36 × 3 = 108,
48/36 = 48 × 3/36 × 3 = 144/108
Subtract the two like fractions:
42/108 - 144/108 = 42 - 144/108 = -102/108
After reducing the fraction, the answer is -17/18

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