Subtract 20/81 from 70/42
1st number: 1 28/42, 2nd number: 20/81
70/42 - 20/81 is 115/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 81 is 1134
Next, find the equivalent fraction of both fractional numbers with denominator 1134 - For the 1st fraction, since 42 × 27 = 1134,
70/42 = 70 × 27/42 × 27 = 1890/1134 - Likewise, for the 2nd fraction, since 81 × 14 = 1134,
20/81 = 20 × 14/81 × 14 = 280/1134 - Subtract the two like fractions:
1890/1134 - 280/1134 = 1890 - 280/1134 = 1610/1134 - After reducing the fraction, the answer is 115/81
- In mixed form: 134/81
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