Subtract 60/28 from 21/30, Solve 21/30

Subtract 60/28 from 21/30

1^st number: 21/30, 2^nd number: 2 4/28

21/30 - 60/28 is -101/70.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 28 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 30 × 14 = 420,
21/30 = 21 × 14/30 × 14 = 294/420
Likewise, for the 2nd fraction, since 28 × 15 = 420,
60/28 = 60 × 15/28 × 15 = 900/420
Subtract the two like fractions:
294/420 - 900/420 = 294 - 900/420 = -606/420
After reducing the fraction, the answer is -101/70

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