Subtract 20/30 from 15/84, Solve 15/84

Subtract 20/30 from 15/84

15/84 - 20/30 is -41/84.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 30 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 84 × 5 = 420,
15/84 = 15 × 5/84 × 5 = 75/420
Likewise, for the 2nd fraction, since 30 × 14 = 420,
20/30 = 20 × 14/30 × 14 = 280/420
Subtract the two like fractions:
75/420 - 280/420 = 75 - 280/420 = -205/420
After reducing the fraction, the answer is -41/84

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