Subtract 90/8 from 15/30, Solve 15/30

Subtract 90/8 from 15/30

1^st number: 15/30, 2^nd number: 11 2/8

15/30 - 90/8 is -43/4.

Find the least common denominator or LCM of the two denominators:
LCM of 30 and 8 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 30 × 4 = 120,
15/30 = 15 × 4/30 × 4 = 60/120
Likewise, for the 2nd fraction, since 8 × 15 = 120,
90/8 = 90 × 15/8 × 15 = 1350/120
Subtract the two like fractions:
60/120 - 1350/120 = 60 - 1350/120 = -1290/120
After reducing the fraction, the answer is -43/4

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