Subtract 96/72 from 21/28, Solve 21/28

Subtract 96/72 from 21/28

1^st number: 21/28, 2^nd number: 1 24/72

21/28 - 96/72 is -7/12.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 72 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 28 × 18 = 504,
21/28 = 21 × 18/28 × 18 = 378/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
96/72 = 96 × 7/72 × 7 = 672/504
Subtract the two like fractions:
378/504 - 672/504 = 378 - 672/504 = -294/504
After reducing the fraction, the answer is -7/12

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