Subtract 63/42 from 54/64, Solve 54/64

Subtract 63/42 from 54/64

1^st number: 54/64, 2^nd number: 1 21/42

54/64 - 63/42 is -21/32.

Find the least common denominator or LCM of the two denominators:
LCM of 64 and 42 is 1344

Next, find the equivalent fraction of both fractional numbers with denominator 1344
For the 1st fraction, since 64 × 21 = 1344,
54/64 = 54 × 21/64 × 21 = 1134/1344
Likewise, for the 2nd fraction, since 42 × 32 = 1344,
63/42 = 63 × 32/42 × 32 = 2016/1344
Subtract the two like fractions:
1134/1344 - 2016/1344 = 1134 - 2016/1344 = -882/1344
After reducing the fraction, the answer is -21/32

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