Subtract 9/64 from 21/28, Solve 21/28

Subtract 9/64 from 21/28

21/28 - 9/64 is 39/64.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 64 is 448

Next, find the equivalent fraction of both fractional numbers with denominator 448
For the 1st fraction, since 28 × 16 = 448,
21/28 = 21 × 16/28 × 16 = 336/448
Likewise, for the 2nd fraction, since 64 × 7 = 448,
9/64 = 9 × 7/64 × 7 = 63/448
Subtract the two like fractions:
336/448 - 63/448 = 336 - 63/448 = 273/448
After reducing the fraction, the answer is 39/64

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