Subtract 64/9 from 21/28, Solve 21/28

Subtract 64/9 from 21/28

1^st number: 21/28, 2^nd number: 7 1/9

21/28 - 64/9 is -229/36.

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,
64/9 = 64 × 28/9 × 28 = 1792/252
Subtract the two like fractions:
189/252 - 1792/252 = 189 - 1792/252 = -1603/252
After reducing the fraction, the answer is -229/36

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