Subtract 16/15 from 21/28, Solve 21/28

Subtract 16/15 from 21/28

1^st number: 21/28, 2^nd number: 1 1/15

21/28 - 16/15 is -19/60.

Find the least common denominator or LCM of the two denominators:
LCM of 28 and 15 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 28 × 15 = 420,
21/28 = 21 × 15/28 × 15 = 315/420
Likewise, for the 2nd fraction, since 15 × 28 = 420,
16/15 = 16 × 28/15 × 28 = 448/420
Subtract the two like fractions:
315/420 - 448/420 = 315 - 448/420 = -133/420
After reducing the fraction, the answer is -19/60

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