Subtract 80/7 from 15/40, Solve 15/40

Subtract 80/7 from 15/40

1^st number: 15/40, 2^nd number: 11 3/7

15/40 - 80/7 is -619/56.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 7 is 280

Next, find the equivalent fraction of both fractional numbers with denominator 280
For the 1st fraction, since 40 × 7 = 280,
15/40 = 15 × 7/40 × 7 = 105/280
Likewise, for the 2nd fraction, since 7 × 40 = 280,
80/7 = 80 × 40/7 × 40 = 3200/280
Subtract the two like fractions:
105/280 - 3200/280 = 105 - 3200/280 = -3095/280
After reducing the fraction, the answer is -619/56

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