Subtract 20/12 from 15/54, Solve 15/54

Subtract 20/12 from 15/54

1^st number: 15/54, 2^nd number: 1 8/12

15/54 - 20/12 is -25/18.

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,
15/54 = 15 × 2/54 × 2 = 30/108
Likewise, for the 2nd fraction, since 12 × 9 = 108,
20/12 = 20 × 9/12 × 9 = 180/108
Subtract the two like fractions:
30/108 - 180/108 = 30 - 180/108 = -150/108
After reducing the fraction, the answer is -25/18

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