Subtract 1/81 from 21/18
1st number: 1 3/18, 2nd number: 1/81
21/18 - 1/81 is 187/162.
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,
21/18 = 21 × 9/18 × 9 = 189/162 - Likewise, for the 2nd fraction, since 81 × 2 = 162,
1/81 = 1 × 2/81 × 2 = 2/162 - Subtract the two like fractions:
189/162 - 2/162 = 189 - 2/162 = 187/162 - In mixed form: 125/162
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