Subtract 84/9 from 81/30
1st number: 2 21/30, 2nd number: 9 3/9
81/30 - 84/9 is -199/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 9 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
81/30 = 81 × 3/30 × 3 = 243/90 - Likewise, for the 2nd fraction, since 9 × 10 = 90,
84/9 = 84 × 10/9 × 10 = 840/90 - Subtract the two like fractions:
243/90 - 840/90 = 243 - 840/90 = -597/90 - After reducing the fraction, the answer is -199/30
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 81/60-84/9 81/30-84/18 81/90-84/9 81/30-84/27 81/30-84/45 81/30-84/63