Subtract 81/8 from 56/21, Solve 2 14/21

Subtract 81/8 from 56/21

1^st number: 2 14/21, 2^nd number: 10 1/8

56/21 - 81/8 is -179/24.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 8 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 21 × 8 = 168,
56/21 = 56 × 8/21 × 8 = 448/168
Likewise, for the 2nd fraction, since 8 × 21 = 168,
81/8 = 81 × 21/8 × 21 = 1701/168
Subtract the two like fractions:
448/168 - 1701/168 = 448 - 1701/168 = -1253/168
After reducing the fraction, the answer is -179/24

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