Subtract 81/18 from 27/42
1st number: 27/42, 2nd number: 4 9/18
27/42 - 81/18 is -27/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 42 × 3 = 126,
27/42 = 27 × 3/42 × 3 = 81/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
81/18 = 81 × 7/18 × 7 = 567/126 - Subtract the two like fractions:
81/126 - 567/126 = 81 - 567/126 = -486/126 - After reducing the fraction, the answer is -27/7
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