Subtract 15/80 from 90/7, Solve 12 6/7

Subtract 15/80 from 90/7

1^st number: 12 6/7, 2^nd number: 15/80

90/7 - 15/80 is 1419/112.

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

Next, find the equivalent fraction of both fractional numbers with denominator 560
For the 1st fraction, since 7 × 80 = 560,
90/7 = 90 × 80/7 × 80 = 7200/560
Likewise, for the 2nd fraction, since 80 × 7 = 560,
15/80 = 15 × 7/80 × 7 = 105/560
Subtract the two like fractions:
7200/560 - 105/560 = 7200 - 105/560 = 7095/560
After reducing the fraction, the answer is 1419/112
In mixed form: 1275/112

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