Subtract 90/81 from 8/9
1st number: 8/9, 2nd number: 1 9/81
8/9 - 90/81 is -2/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 81 is 81
Next, find the equivalent fraction of both fractional numbers with denominator 81 - For the 1st fraction, since 9 × 9 = 81,
8/9 = 8 × 9/9 × 9 = 72/81 - Likewise, for the 2nd fraction, since 81 × 1 = 81,
90/81 = 90 × 1/81 × 1 = 90/81 - Subtract the two like fractions:
72/81 - 90/81 = 72 - 90/81 = -18/81 - After reducing the fraction, the answer is -2/9
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 16/9-90/81 8/18-90/81 24/9-90/81 8/27-90/81 40/9-90/81 8/45-90/81 56/9-90/81 8/63-90/81