Subtract 21/7 from 8/15, Solve 8/15

Subtract 21/7 from 8/15

1^st number: 8/15, 2^nd number: 3 0/7

8/15 - 21/7 is -37/15.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 7 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 15 × 7 = 105,
8/15 = 8 × 7/15 × 7 = 56/105
Likewise, for the 2nd fraction, since 7 × 15 = 105,
21/7 = 21 × 15/7 × 15 = 315/105
Subtract the two like fractions:
56/105 - 315/105 = 56 - 315/105 = -259/105
After reducing the fraction, the answer is -37/15

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