Subtract 20/81 from 1/2
1/2 - 20/81 is 41/162.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 2 and 81 is 162
Next, find the equivalent fraction of both fractional numbers with denominator 162 - For the 1st fraction, since 2 × 81 = 162,
1/2 = 1 × 81/2 × 81 = 81/162 - Likewise, for the 2nd fraction, since 81 × 2 = 162,
20/81 = 20 × 2/81 × 2 = 40/162 - Subtract the two like fractions:
81/162 - 40/162 = 81 - 40/162 = 41/162
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