Subtract 21/20 from 12/27, Solve 12/27

Subtract 21/20 from 12/27

1^st number: 12/27, 2^nd number: 1 1/20

12/27 - 21/20 is -109/180.

Find the least common denominator or LCM of the two denominators:
LCM of 27 and 20 is 540

Next, find the equivalent fraction of both fractional numbers with denominator 540
For the 1st fraction, since 27 × 20 = 540,
12/27 = 12 × 20/27 × 20 = 240/540
Likewise, for the 2nd fraction, since 20 × 27 = 540,
21/20 = 21 × 27/20 × 27 = 567/540
Subtract the two like fractions:
240/540 - 567/540 = 240 - 567/540 = -327/540
After reducing the fraction, the answer is -109/180

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