Subtract 80/27 from 21/28, Solve 21/28

Subtract 80/27 from 21/28

1^st number: 21/28, 2^nd number: 2 26/27

21/28 - 80/27 is -239/108.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 27 is 756

Next, find the equivalent fraction of both fractional numbers with denominator 756
For the 1st fraction, since 28 × 27 = 756,
21/28 = 21 × 27/28 × 27 = 567/756
Likewise, for the 2nd fraction, since 27 × 28 = 756,
80/27 = 80 × 28/27 × 28 = 2240/756
Subtract the two like fractions:
567/756 - 2240/756 = 567 - 2240/756 = -1673/756
After reducing the fraction, the answer is -239/108

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