Subtract 90/8 from 7/15, Solve 7/15

Subtract 90/8 from 7/15

1^st number: 7/15, 2^nd number: 11 2/8

7/15 - 90/8 is -647/60.

Find the least common denominator or LCM of the two denominators:
LCM of 15 and 8 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 15 × 8 = 120,
7/15 = 7 × 8/15 × 8 = 56/120
Likewise, for the 2nd fraction, since 8 × 15 = 120,
90/8 = 90 × 15/8 × 15 = 1350/120
Subtract the two like fractions:
56/120 - 1350/120 = 56 - 1350/120 = -1294/120
After reducing the fraction, the answer is -647/60

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