Subtract 72/81 from 1/2
1/2 - 72/81 is -7/18.
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,
72/81 = 72 × 2/81 × 2 = 144/162 - Subtract the two like fractions:
81/162 - 144/162 = 81 - 144/162 = -63/162 - After reducing the fraction, the answer is -7/18
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