Subtract 21/81 from 7/9
7/9 - 21/81 is 14/27.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 81 is 81
Next, find the equivalent fraction of both fractional numbers with denominator 81 - For the 1st fraction, since 9 × 9 = 81,
7/9 = 7 × 9/9 × 9 = 63/81 - Likewise, for the 2nd fraction, since 81 × 1 = 81,
21/81 = 21 × 1/81 × 1 = 21/81 - Subtract the two like fractions:
63/81 - 21/81 = 63 - 21/81 = 42/81 - After reducing the fraction, the answer is 14/27
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