Subtract 8/21 from 40/15, Solve 2 10/15

Subtract 8/21 from 40/15

1^st number: 2 10/15, 2^nd number: 8/21

40/15 - 8/21 is 16/7.

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,
40/15 = 40 × 7/15 × 7 = 280/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
8/21 = 8 × 5/21 × 5 = 40/105
Subtract the two like fractions:
280/105 - 40/105 = 280 - 40/105 = 240/105
After reducing the fraction, the answer is 16/7
In mixed form: 22/7

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