Subtract 8/21 from 56/18, Solve 3 2/18

Subtract 8/21 from 56/18

1^st number: 3 2/18, 2^nd number: 8/21

56/18 - 8/21 is 172/63.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126

Next, find the equivalent fraction of both fractional numbers with denominator 126
For the 1st fraction, since 18 × 7 = 126,
56/18 = 56 × 7/18 × 7 = 392/126
Likewise, for the 2nd fraction, since 21 × 6 = 126,
8/21 = 8 × 6/21 × 6 = 48/126
Subtract the two like fractions:
392/126 - 48/126 = 392 - 48/126 = 344/126
After reducing the fraction, the answer is 172/63
In mixed form: 246/63

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