Subtract 42/64 from 5/21, Solve 5/21

Subtract 42/64 from 5/21

5/21 - 42/64 is -281/672.

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,
5/21 = 5 × 64/21 × 64 = 320/1344
Likewise, for the 2nd fraction, since 64 × 21 = 1344,
42/64 = 42 × 21/64 × 21 = 882/1344
Subtract the two like fractions:
320/1344 - 882/1344 = 320 - 882/1344 = -562/1344
After reducing the fraction, the answer is -281/672

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