Subtract 12/81 from 5/42
5/42 - 12/81 is -11/378.
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,
5/42 = 5 × 27/42 × 27 = 135/1134 - Likewise, for the 2nd fraction, since 81 × 14 = 1134,
12/81 = 12 × 14/81 × 14 = 168/1134 - Subtract the two like fractions:
135/1134 - 168/1134 = 135 - 168/1134 = -33/1134 - After reducing the fraction, the answer is -11/378
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