Subtract 42/96 from 15/21, Solve 15/21

Subtract 42/96 from 15/21

15/21 - 42/96 is 31/112.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 96 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 96 × 7 = 672,
42/96 = 42 × 7/96 × 7 = 294/672
Subtract the two like fractions:
480/672 - 294/672 = 480 - 294/672 = 186/672
After reducing the fraction, the answer is 31/112

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