Subtract 75/63 from 20/84, Solve 20/84

Subtract 75/63 from 20/84

1^st number: 20/84, 2^nd number: 1 12/63

20/84 - 75/63 is -20/21.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 63 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 84 × 3 = 252,
20/84 = 20 × 3/84 × 3 = 60/252
Likewise, for the 2nd fraction, since 63 × 4 = 252,
75/63 = 75 × 4/63 × 4 = 300/252
Subtract the two like fractions:
60/252 - 300/252 = 60 - 300/252 = -240/252
After reducing the fraction, the answer is -20/21

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