Subtract 21/20 from 12/54, Solve 12/54

Subtract 21/20 from 12/54

1^st number: 12/54, 2^nd number: 1 1/20

12/54 - 21/20 is -149/180.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 20 is 540

Next, find the equivalent fraction of both fractional numbers with denominator 540
For the 1st fraction, since 54 × 10 = 540,
12/54 = 12 × 10/54 × 10 = 120/540
Likewise, for the 2nd fraction, since 20 × 27 = 540,
21/20 = 21 × 27/20 × 27 = 567/540
Subtract the two like fractions:
120/540 - 567/540 = 120 - 567/540 = -447/540
After reducing the fraction, the answer is -149/180

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