Subtract 20/21 from 15/60, Solve 15/60

Subtract 20/21 from 15/60

15/60 - 20/21 is -59/84.

Find the least common denominator or LCM of the two denominators:
LCM of 60 and 21 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 60 × 7 = 420,
15/60 = 15 × 7/60 × 7 = 105/420
Likewise, for the 2nd fraction, since 21 × 20 = 420,
20/21 = 20 × 20/21 × 20 = 400/420
Subtract the two like fractions:
105/420 - 400/420 = 105 - 400/420 = -295/420
After reducing the fraction, the answer is -59/84

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