Subtract 70/42 from 20/81
1st number: 20/81, 2nd number: 1 28/42
20/81 - 70/42 is -115/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 42 is 1134
Next, find the equivalent fraction of both fractional numbers with denominator 1134 - For the 1st fraction, since 81 × 14 = 1134,
20/81 = 20 × 14/81 × 14 = 280/1134 - Likewise, for the 2nd fraction, since 42 × 27 = 1134,
70/42 = 70 × 27/42 × 27 = 1890/1134 - Subtract the two like fractions:
280/1134 - 1890/1134 = 280 - 1890/1134 = -1610/1134 - After reducing the fraction, the answer is -115/81
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