Subtract 15/25 from 20/84, Solve 20/84

Subtract 15/25 from 20/84

20/84 - 15/25 is -38/105.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 25 is 2100

Next, find the equivalent fraction of both fractional numbers with denominator 2100
For the 1st fraction, since 84 × 25 = 2100,
20/84 = 20 × 25/84 × 25 = 500/2100
Likewise, for the 2nd fraction, since 25 × 84 = 2100,
15/25 = 15 × 84/25 × 84 = 1260/2100
Subtract the two like fractions:
500/2100 - 1260/2100 = 500 - 1260/2100 = -760/2100
After reducing the fraction, the answer is -38/105

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