Subtract 8/7 from 5/15, Solve 5/15

Subtract 8/7 from 5/15

1^st number: 5/15, 2^nd number: 1 1/7

5/15 - 8/7 is -17/21.

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,
5/15 = 5 × 7/15 × 7 = 35/105
Likewise, for the 2nd fraction, since 7 × 15 = 105,
8/7 = 8 × 15/7 × 15 = 120/105
Subtract the two like fractions:
35/105 - 120/105 = 35 - 120/105 = -85/105
After reducing the fraction, the answer is -17/21

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