Subtract 1/18 from 21/81
21/81 - 1/18 is 11/54.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 18 is 162
Next, find the equivalent fraction of both fractional numbers with denominator 162 - For the 1st fraction, since 81 × 2 = 162,
21/81 = 21 × 2/81 × 2 = 42/162 - Likewise, for the 2nd fraction, since 18 × 9 = 162,
1/18 = 1 × 9/18 × 9 = 9/162 - Subtract the two like fractions:
42/162 - 9/162 = 42 - 9/162 = 33/162 - After reducing the fraction, the answer is 11/54
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