Subtract 9/21 from 90/12, Solve 7 6/12

Subtract 9/21 from 90/12

1^st number: 7 6/12, 2^nd number: 9/21

90/12 - 9/21 is 99/14.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
90/12 = 90 × 7/12 × 7 = 630/84
Likewise, for the 2nd fraction, since 21 × 4 = 84,
9/21 = 9 × 4/21 × 4 = 36/84
Subtract the two like fractions:
630/84 - 36/84 = 630 - 36/84 = 594/84
After reducing the fraction, the answer is 99/14
In mixed form: 71/14

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