Subtract 80/9 from 21/28, Solve 21/28

Subtract 80/9 from 21/28

1^st number: 21/28, 2^nd number: 8 8/9

21/28 - 80/9 is -293/36.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 9 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 28 × 9 = 252,
21/28 = 21 × 9/28 × 9 = 189/252
Likewise, for the 2nd fraction, since 9 × 28 = 252,
80/9 = 80 × 28/9 × 28 = 2240/252
Subtract the two like fractions:
189/252 - 2240/252 = 189 - 2240/252 = -2051/252
After reducing the fraction, the answer is -293/36

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