Subtract 84/81 from 42/20
1st number: 2 2/20, 2nd number: 1 3/81
42/20 - 84/81 is 287/270.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 81 is 1620
Next, find the equivalent fraction of both fractional numbers with denominator 1620 - For the 1st fraction, since 20 × 81 = 1620,
42/20 = 42 × 81/20 × 81 = 3402/1620 - Likewise, for the 2nd fraction, since 81 × 20 = 1620,
84/81 = 84 × 20/81 × 20 = 1680/1620 - Subtract the two like fractions:
3402/1620 - 1680/1620 = 3402 - 1680/1620 = 1722/1620 - After reducing the fraction, the answer is 287/270
- In mixed form: 117/270
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