Subtract 20/27 from 42/81
42/81 - 20/27 is -2/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 27 is 81
Next, find the equivalent fraction of both fractional numbers with denominator 81 - For the 1st fraction, since 81 × 1 = 81,
42/81 = 42 × 1/81 × 1 = 42/81 - Likewise, for the 2nd fraction, since 27 × 3 = 81,
20/27 = 20 × 3/27 × 3 = 60/81 - Subtract the two like fractions:
42/81 - 60/81 = 42 - 60/81 = -18/81 - After reducing the fraction, the answer is -2/9
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