Subtract 80/42 from 90/81
1st number: 1 9/81, 2nd number: 1 38/42
90/81 - 80/42 is -50/63.
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,
90/81 = 90 × 14/81 × 14 = 1260/1134 - Likewise, for the 2nd fraction, since 42 × 27 = 1134,
80/42 = 80 × 27/42 × 27 = 2160/1134 - Subtract the two like fractions:
1260/1134 - 2160/1134 = 1260 - 2160/1134 = -900/1134 - After reducing the fraction, the answer is -50/63
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