Subtract 18/21 from 81/8, Solve 10 1/8

Subtract 18/21 from 81/8

1^st number: 10 1/8, 2^nd number: 18/21

81/8 - 18/21 is 519/56.

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

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 8 × 21 = 168,
81/8 = 81 × 21/8 × 21 = 1701/168
Likewise, for the 2nd fraction, since 21 × 8 = 168,
18/21 = 18 × 8/21 × 8 = 144/168
Subtract the two like fractions:
1701/168 - 144/168 = 1701 - 144/168 = 1557/168
After reducing the fraction, the answer is 519/56
In mixed form: 915/56

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