Subtract 4/81 from 20/18
1st number: 1 2/18, 2nd number: 4/81
20/18 - 4/81 is 86/81.
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,
20/18 = 20 × 9/18 × 9 = 180/162 - Likewise, for the 2nd fraction, since 81 × 2 = 162,
4/81 = 4 × 2/81 × 2 = 8/162 - Subtract the two like fractions:
180/162 - 8/162 = 180 - 8/162 = 172/162 - After reducing the fraction, the answer is 86/81
- In mixed form: 15/81
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