Subtract 42/81 from 9/18
9/18 - 42/81 is -1/54.
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,
9/18 = 9 × 9/18 × 9 = 81/162 - Likewise, for the 2nd fraction, since 81 × 2 = 162,
42/81 = 42 × 2/81 × 2 = 84/162 - Subtract the two like fractions:
81/162 - 84/162 = 81 - 84/162 = -3/162 - After reducing the fraction, the answer is -1/54
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