Subtract 10/84 from 90/12, Solve 7 6/12

Subtract 10/84 from 90/12

1^st number: 7 6/12, 2^nd number: 10/84

90/12 - 10/84 is 155/21.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 84 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 84 × 1 = 84,
10/84 = 10 × 1/84 × 1 = 10/84
Subtract the two like fractions:
630/84 - 10/84 = 630 - 10/84 = 620/84
After reducing the fraction, the answer is 155/21
In mixed form: 78/21

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