Subtract 10/18 from 20/81
20/81 - 10/18 is -25/81.
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,
20/81 = 20 × 2/81 × 2 = 40/162 - Likewise, for the 2nd fraction, since 18 × 9 = 162,
10/18 = 10 × 9/18 × 9 = 90/162 - Subtract the two like fractions:
40/162 - 90/162 = 40 - 90/162 = -50/162 - After reducing the fraction, the answer is -25/81
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