Subtract 81/56 from 20/84, Solve 20/84

Subtract 81/56 from 20/84

1^st number: 20/84, 2^nd number: 1 25/56

20/84 - 81/56 is -29/24.

Find the least common denominator or LCM of the two denominators:
LCM of 84 and 56 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 84 × 2 = 168,
20/84 = 20 × 2/84 × 2 = 40/168
Likewise, for the 2nd fraction, since 56 × 3 = 168,
81/56 = 81 × 3/56 × 3 = 243/168
Subtract the two like fractions:
40/168 - 243/168 = 40 - 243/168 = -203/168
After reducing the fraction, the answer is -29/24

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