Subtract 21/24 from 90/7, Solve 12 6/7

Subtract 21/24 from 90/7

1^st number: 12 6/7, 2^nd number: 21/24

90/7 - 21/24 is 671/56.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 24 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 7 × 24 = 168,
90/7 = 90 × 24/7 × 24 = 2160/168
Likewise, for the 2nd fraction, since 24 × 7 = 168,
21/24 = 21 × 7/24 × 7 = 147/168
Subtract the two like fractions:
2160/168 - 147/168 = 2160 - 147/168 = 2013/168
After reducing the fraction, the answer is 671/56
In mixed form: 1155/56

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