Subtract 8/18 from 5/81
5/81 - 8/18 is -31/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 18 is 162
Next, find the equivalent fraction of both fractional numbers with denominator 162 - For the 1st fraction, since 81 × 2 = 162,
5/81 = 5 × 2/81 × 2 = 10/162 - Likewise, for the 2nd fraction, since 18 × 9 = 162,
8/18 = 8 × 9/18 × 9 = 72/162 - Subtract the two like fractions:
10/162 - 72/162 = 10 - 72/162 = -62/162 - After reducing the fraction, the answer is -31/81
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