Subtract 70/21 from 90/6, Solve 15 0/6

Subtract 70/21 from 90/6

1^st number: 15 0/6, 2^nd number: 3 7/21

90/6 - 70/21 is 35/3.

Find the least common denominator or LCM of the two denominators:
LCM of 6 and 21 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 21 × 2 = 42,
70/21 = 70 × 2/21 × 2 = 140/42
Subtract the two like fractions:
630/42 - 140/42 = 630 - 140/42 = 490/42
After reducing the fraction, the answer is 35/3
In mixed form: 112/3

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