Subtract 28/81 from 42/18
1st number: 2 6/18, 2nd number: 28/81
42/18 - 28/81 is 161/81.
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,
42/18 = 42 × 9/18 × 9 = 378/162 - Likewise, for the 2nd fraction, since 81 × 2 = 162,
28/81 = 28 × 2/81 × 2 = 56/162 - Subtract the two like fractions:
378/162 - 56/162 = 378 - 56/162 = 322/162 - After reducing the fraction, the answer is 161/81
- In mixed form: 180/81
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