Subtract 20/9 from 90/81
1st number: 1 9/81, 2nd number: 2 2/9
90/81 - 20/9 is -10/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 9 is 81
Next, find the equivalent fraction of both fractional numbers with denominator 81 - For the 1st fraction, since 81 × 1 = 81,
90/81 = 90 × 1/81 × 1 = 90/81 - Likewise, for the 2nd fraction, since 9 × 9 = 81,
20/9 = 20 × 9/9 × 9 = 180/81 - Subtract the two like fractions:
90/81 - 180/81 = 90 - 180/81 = -90/81 - After reducing the fraction, the answer is -10/9
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