Subtract 90/42 from 84/12, Solve 7 0/12

Subtract 90/42 from 84/12

1^st number: 7 0/12, 2^nd number: 2 6/42

84/12 - 90/42 is 34/7.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 42 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
84/12 = 84 × 7/12 × 7 = 588/84
Likewise, for the 2nd fraction, since 42 × 2 = 84,
90/42 = 90 × 2/42 × 2 = 180/84
Subtract the two like fractions:
588/84 - 180/84 = 588 - 180/84 = 408/84
After reducing the fraction, the answer is 34/7
In mixed form: 46/7

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