Subtract 70/81 from 20/27
20/27 - 70/81 is -10/81.
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,
20/27 = 20 × 3/27 × 3 = 60/81 - Likewise, for the 2nd fraction, since 81 × 1 = 81,
70/81 = 70 × 1/81 × 1 = 70/81 - Subtract the two like fractions:
60/81 - 70/81 = 60 - 70/81 = -10/81
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