Subtract 21/9 from 30/80
1st number: 30/80, 2nd number: 2 3/9
30/80 - 21/9 is -47/24.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 9 is 720
Next, find the equivalent fraction of both fractional numbers with denominator 720 - For the 1st fraction, since 80 × 9 = 720,
30/80 = 30 × 9/80 × 9 = 270/720 - Likewise, for the 2nd fraction, since 9 × 80 = 720,
21/9 = 21 × 80/9 × 80 = 1680/720 - Subtract the two like fractions:
270/720 - 1680/720 = 270 - 1680/720 = -1410/720 - After reducing the fraction, the answer is -47/24
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 60/80-21/9 30/80-42/9 30/80-21/18 90/80-21/9 30/80-63/9 30/80-21/27 30/80-21/45 30/80-21/63