Subtract 81/56 from 3/42
1st number: 3/42, 2nd number: 1 25/56
3/42 - 81/56 is -11/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 56 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 42 × 4 = 168,
3/42 = 3 × 4/42 × 4 = 12/168 - Likewise, for the 2nd fraction, since 56 × 3 = 168,
81/56 = 81 × 3/56 × 3 = 243/168 - Subtract the two like fractions:
12/168 - 243/168 = 12 - 243/168 = -231/168 - After reducing the fraction, the answer is -11/8
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