Subtract 90/32 from 15/21, Solve 15/21

Subtract 90/32 from 15/21

1^st number: 15/21, 2^nd number: 2 26/32

15/21 - 90/32 is -235/112.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 32 is 672

Next, find the equivalent fraction of both fractional numbers with denominator 672
For the 1st fraction, since 21 × 32 = 672,
15/21 = 15 × 32/21 × 32 = 480/672
Likewise, for the 2nd fraction, since 32 × 21 = 672,
90/32 = 90 × 21/32 × 21 = 1890/672
Subtract the two like fractions:
480/672 - 1890/672 = 480 - 1890/672 = -1410/672
After reducing the fraction, the answer is -235/112

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