Subtract 18/21 from 9/64, Solve 9/64

Subtract 18/21 from 9/64

9/64 - 18/21 is -321/448.

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,
9/64 = 9 × 21/64 × 21 = 189/1344
Likewise, for the 2nd fraction, since 21 × 64 = 1344,
18/21 = 18 × 64/21 × 64 = 1152/1344
Subtract the two like fractions:
189/1344 - 1152/1344 = 189 - 1152/1344 = -963/1344
After reducing the fraction, the answer is -321/448

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