Subtract 20/7 from 15/80, Solve 15/80

Subtract 20/7 from 15/80

1^st number: 15/80, 2^nd number: 2 6/7

15/80 - 20/7 is -299/112.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 7 is 560

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 80 × 7 = 560,
15/80 = 15 × 7/80 × 7 = 105/560
Likewise, for the 2nd fraction, since 7 × 80 = 560,
20/7 = 20 × 80/7 × 80 = 1600/560
Subtract the two like fractions:
105/560 - 1600/560 = 105 - 1600/560 = -1495/560
After reducing the fraction, the answer is -299/112

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