Subtract 21/81 from 45/54
45/54 - 21/81 is 31/54.
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,
45/54 = 45 × 3/54 × 3 = 135/162 - Likewise, for the 2nd fraction, since 81 × 2 = 162,
21/81 = 21 × 2/81 × 2 = 42/162 - Subtract the two like fractions:
135/162 - 42/162 = 135 - 42/162 = 93/162 - After reducing the fraction, the answer is 31/54
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