Subtract 20/7 from 90/5, Solve 18 0/5

Subtract 20/7 from 90/5

1^st number: 18 0/5, 2^nd number: 2 6/7

90/5 - 20/7 is 106/7.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 7 is 35

Next, find the equivalent fraction of both fractional numbers with denominator 35
For the 1st fraction, since 5 × 7 = 35,
90/5 = 90 × 7/5 × 7 = 630/35
Likewise, for the 2nd fraction, since 7 × 5 = 35,
20/7 = 20 × 5/7 × 5 = 100/35
Subtract the two like fractions:
630/35 - 100/35 = 630 - 100/35 = 530/35
After reducing the fraction, the answer is 106/7
In mixed form: 151/7

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