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

Subtract 3/21 from 56/18

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

56/18 - 3/21 is 187/63.

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,
3/21 = 3 × 6/21 × 6 = 18/126
Subtract the two like fractions:
392/126 - 18/126 = 392 - 18/126 = 374/126
After reducing the fraction, the answer is 187/63
In mixed form: 261/63

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