Subtract 15/30 from 7/40, Solve 7/40

Subtract 15/30 from 7/40

7/40 - 15/30 is -13/40.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 30 is 120

Next, find the equivalent fraction of both fractional numbers with denominator 120
For the 1st fraction, since 40 × 3 = 120,
7/40 = 7 × 3/40 × 3 = 21/120
Likewise, for the 2nd fraction, since 30 × 4 = 120,
15/30 = 15 × 4/30 × 4 = 60/120
Subtract the two like fractions:
21/120 - 60/120 = 21 - 60/120 = -39/120
After reducing the fraction, the answer is -13/40

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