Subtract 24/12 from 81/42
1st number: 1 39/42, 2nd number: 2 0/12
81/42 - 24/12 is -1/14.
Steps for subtracting fractions
- 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,
24/12 = 24 × 7/12 × 7 = 168/84 - Subtract the two like fractions:
162/84 - 168/84 = 162 - 168/84 = -6/84 - After reducing the fraction, the answer is -1/14
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