Subtract 20/7 from 90/6, Solve 15 0/6

Subtract 20/7 from 90/6

1^st number: 15 0/6, 2^nd number: 2 6/7

90/6 - 20/7 is 85/7.

Find the least common denominator or LCM of the two denominators:
LCM of 6 and 7 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 6 × 7 = 42,
90/6 = 90 × 7/6 × 7 = 630/42
Likewise, for the 2nd fraction, since 7 × 6 = 42,
20/7 = 20 × 6/7 × 6 = 120/42
Subtract the two like fractions:
630/42 - 120/42 = 630 - 120/42 = 510/42
After reducing the fraction, the answer is 85/7
In mixed form: 121/7

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