Subtract 90/21 from 27/64, Solve 27/64

Subtract 90/21 from 27/64

1^st number: 27/64, 2^nd number: 4 6/21

27/64 - 90/21 is -1731/448.

Find the least common denominator or LCM of the two denominators:
LCM of 64 and 21 is 1344

Next, find the equivalent fraction of both fractional numbers with denominator 1344
For the 1st fraction, since 64 × 21 = 1344,
27/64 = 27 × 21/64 × 21 = 567/1344
Likewise, for the 2nd fraction, since 21 × 64 = 1344,
90/21 = 90 × 64/21 × 64 = 5760/1344
Subtract the two like fractions:
567/1344 - 5760/1344 = 567 - 5760/1344 = -5193/1344
After reducing the fraction, the answer is -1731/448

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