Subtract 80/49 from 15/40, Solve 15/40

Subtract 80/49 from 15/40

1^st number: 15/40, 2^nd number: 1 31/49

15/40 - 80/49 is -493/392.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 49 is 1960

Next, find the equivalent fraction of both fractional numbers with denominator 1960
For the 1st fraction, since 40 × 49 = 1960,
15/40 = 15 × 49/40 × 49 = 735/1960
Likewise, for the 2nd fraction, since 49 × 40 = 1960,
80/49 = 80 × 40/49 × 40 = 3200/1960
Subtract the two like fractions:
735/1960 - 3200/1960 = 735 - 3200/1960 = -2465/1960
After reducing the fraction, the answer is -493/392

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