Subtract 50/15 from 12/40, Solve 12/40

Subtract 50/15 from 12/40

1^st number: 12/40, 2^nd number: 3 5/15

12/40 - 50/15 is -91/30.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 15 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 40 × 3 = 120,
12/40 = 12 × 3/40 × 3 = 36/120
Likewise, for the 2nd fraction, since 15 × 8 = 120,
50/15 = 50 × 8/15 × 8 = 400/120
Subtract the two like fractions:
36/120 - 400/120 = 36 - 400/120 = -364/120
After reducing the fraction, the answer is -91/30

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