Subtract 18/81 from 3/42
3/42 - 18/81 is -19/126.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 81 is 1134
Next, find the equivalent fraction of both fractional numbers with denominator 1134 - For the 1st fraction, since 42 × 27 = 1134,
3/42 = 3 × 27/42 × 27 = 81/1134 - Likewise, for the 2nd fraction, since 81 × 14 = 1134,
18/81 = 18 × 14/81 × 14 = 252/1134 - Subtract the two like fractions:
81/1134 - 252/1134 = 81 - 252/1134 = -171/1134 - After reducing the fraction, the answer is -19/126
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