Subtract 49/81 from 18/42
18/42 - 49/81 is -100/567.
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,
18/42 = 18 × 27/42 × 27 = 486/1134 - Likewise, for the 2nd fraction, since 81 × 14 = 1134,
49/81 = 49 × 14/81 × 14 = 686/1134 - Subtract the two like fractions:
486/1134 - 686/1134 = 486 - 686/1134 = -200/1134 - After reducing the fraction, the answer is -100/567
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