Subtract 8/12 from 81/42, Solve 1 39/42

Subtract 8/12 from 81/42

1^st number: 1 39/42, 2^nd number: 8/12

81/42 - 8/12 is 53/42.

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

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 42 × 2 = 84,
81/42 = 81 × 2/42 × 2 = 162/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
8/12 = 8 × 7/12 × 7 = 56/84
Subtract the two like fractions:
162/84 - 56/84 = 162 - 56/84 = 106/84
After reducing the fraction, the answer is 53/42
In mixed form: 111/42

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