Subtract 1/27 from 21/81
21/81 - 1/27 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,
21/81 = 21 × 1/81 × 1 = 21/81 - Likewise, for the 2nd fraction, since 27 × 3 = 81,
1/27 = 1 × 3/27 × 3 = 3/81 - Subtract the two like fractions:
21/81 - 3/81 = 21 - 3/81 = 18/81 - After reducing the fraction, the answer is 2/9
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