Subtract 20/81 from 4/18
4/18 - 20/81 is -2/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 81 is 162
Next, find the equivalent fraction of both fractional numbers with denominator 162 - For the 1st fraction, since 18 × 9 = 162,
4/18 = 4 × 9/18 × 9 = 36/162 - Likewise, for the 2nd fraction, since 81 × 2 = 162,
20/81 = 20 × 2/81 × 2 = 40/162 - Subtract the two like fractions:
36/162 - 40/162 = 36 - 40/162 = -4/162 - After reducing the fraction, the answer is -2/81
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