Subtract 81/12 from 7/42
1st number: 7/42, 2nd number: 6 9/12
7/42 - 81/12 is -79/12.
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,
7/42 = 7 × 2/42 × 2 = 14/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
81/12 = 81 × 7/12 × 7 = 567/84 - Subtract the two like fractions:
14/84 - 567/84 = 14 - 567/84 = -553/84 - After reducing the fraction, the answer is -79/12
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