Subtract 12/15 from 10/40, Solve 10/40

Subtract 12/15 from 10/40

10/40 - 12/15 is -11/20.

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,
10/40 = 10 × 3/40 × 3 = 30/120
Likewise, for the 2nd fraction, since 15 × 8 = 120,
12/15 = 12 × 8/15 × 8 = 96/120
Subtract the two like fractions:
30/120 - 96/120 = 30 - 96/120 = -66/120
After reducing the fraction, the answer is -11/20

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