Subtract 15/27 from 21/20, Solve 1 1/20

Subtract 15/27 from 21/20

1^st number: 1 1/20, 2^nd number: 15/27

21/20 - 15/27 is 89/180.

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

Next, find the equivalent fraction of both fractional numbers with denominator 540
For the 1st fraction, since 20 × 27 = 540,
21/20 = 21 × 27/20 × 27 = 567/540
Likewise, for the 2nd fraction, since 27 × 20 = 540,
15/27 = 15 × 20/27 × 20 = 300/540
Subtract the two like fractions:
567/540 - 300/540 = 567 - 300/540 = 267/540
After reducing the fraction, the answer is 89/180

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