Subtract 16/21 from 56/15, Solve 3 11/15

Subtract 16/21 from 56/15

1^st number: 3 11/15, 2^nd number: 16/21

56/15 - 16/21 is 104/35.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 15 × 7 = 105,
56/15 = 56 × 7/15 × 7 = 392/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
16/21 = 16 × 5/21 × 5 = 80/105
Subtract the two like fractions:
392/105 - 80/105 = 392 - 80/105 = 312/105
After reducing the fraction, the answer is 104/35
In mixed form: 234/35

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