Subtract 3/9 from 7/81
7/81 - 3/9 is -20/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 9 is 81
Next, find the equivalent fraction of both fractional numbers with denominator 81 - For the 1st fraction, since 81 × 1 = 81,
7/81 = 7 × 1/81 × 1 = 7/81 - Likewise, for the 2nd fraction, since 9 × 9 = 81,
3/9 = 3 × 9/9 × 9 = 27/81 - Subtract the two like fractions:
7/81 - 27/81 = 7 - 27/81 = -20/81
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