Subtract 81/42 from 12/84
1st number: 12/84, 2nd number: 1 39/42
12/84 - 81/42 is -25/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
12/84 = 12 × 1/84 × 1 = 12/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
81/42 = 81 × 2/42 × 2 = 162/84 - Subtract the two like fractions:
12/84 - 162/84 = 12 - 162/84 = -150/84 - After reducing the fraction, the answer is -25/14
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