Subtract 90/81 from 80/90
1st number: 80/90, 2nd number: 1 9/81
80/90 - 90/81 is -2/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 90 × 9 = 810,
80/90 = 80 × 9/90 × 9 = 720/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
90/81 = 90 × 10/81 × 10 = 900/810 - Subtract the two like fractions:
720/810 - 900/810 = 720 - 900/810 = -180/810 - After reducing the fraction, the answer is -2/9
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