Subtract 15/81 from 7/54
7/54 - 15/81 is -1/18.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 81 is 162
Next, find the equivalent fraction of both fractional numbers with denominator 162 - For the 1st fraction, since 54 × 3 = 162,
7/54 = 7 × 3/54 × 3 = 21/162 - Likewise, for the 2nd fraction, since 81 × 2 = 162,
15/81 = 15 × 2/81 × 2 = 30/162 - Subtract the two like fractions:
21/162 - 30/162 = 21 - 30/162 = -9/162 - After reducing the fraction, the answer is -1/18
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