Subtract 6/64 from 21/90, Solve 21/90

Subtract 6/64 from 21/90

21/90 - 6/64 is 67/480.

Find the least common denominator or LCM of the two denominators:
LCM of 90 and 64 is 2880

Next, find the equivalent fraction of both fractional numbers with denominator 2880
For the 1st fraction, since 90 × 32 = 2880,
21/90 = 21 × 32/90 × 32 = 672/2880
Likewise, for the 2nd fraction, since 64 × 45 = 2880,
6/64 = 6 × 45/64 × 45 = 270/2880
Subtract the two like fractions:
672/2880 - 270/2880 = 672 - 270/2880 = 402/2880
After reducing the fraction, the answer is 67/480

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