Subtract 8/21 from 56/12, Solve 4 8/12

Subtract 8/21 from 56/12

1^st number: 4 8/12, 2^nd number: 8/21

56/12 - 8/21 is 30/7.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
56/12 = 56 × 7/12 × 7 = 392/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
8/21 = 8 × 4/21 × 4 = 32/84
Subtract the two like fractions:
392/84 - 32/84 = 392 - 32/84 = 360/84
After reducing the fraction, the answer is 30/7
In mixed form: 42/7

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