Subtract 90/64 from 2/21, Solve 2/21

Subtract 90/64 from 2/21

1^st number: 2/21, 2^nd number: 1 26/64

2/21 - 90/64 is -881/672.

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,
2/21 = 2 × 64/21 × 64 = 128/1344
Likewise, for the 2nd fraction, since 64 × 21 = 1344,
90/64 = 90 × 21/64 × 21 = 1890/1344
Subtract the two like fractions:
128/1344 - 1890/1344 = 128 - 1890/1344 = -1762/1344
After reducing the fraction, the answer is -881/672

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