Subtract 42/81 from 12/27
12/27 - 42/81 is -2/27.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 81 is 81
Next, find the equivalent fraction of both fractional numbers with denominator 81 - For the 1st fraction, since 27 × 3 = 81,
12/27 = 12 × 3/27 × 3 = 36/81 - Likewise, for the 2nd fraction, since 81 × 1 = 81,
42/81 = 42 × 1/81 × 1 = 42/81 - Subtract the two like fractions:
36/81 - 42/81 = 36 - 42/81 = -6/81 - After reducing the fraction, the answer is -2/27
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