Subtract 27/64 from 3/21, Solve 3/21

Subtract 27/64 from 3/21

3/21 - 27/64 is -125/448.

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

Next, find the equivalent fraction of both fractional numbers with denominator 1344
For the 1st fraction, since 21 × 64 = 1344,
3/21 = 3 × 64/21 × 64 = 192/1344
Likewise, for the 2nd fraction, since 64 × 21 = 1344,
27/64 = 27 × 21/64 × 21 = 567/1344
Subtract the two like fractions:
192/1344 - 567/1344 = 192 - 567/1344 = -375/1344
After reducing the fraction, the answer is -125/448

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