Subtract 80/9 from 21/72
1st number: 21/72, 2nd number: 8 8/9
21/72 - 80/9 is -619/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 9 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 72 × 1 = 72,
21/72 = 21 × 1/72 × 1 = 21/72 - Likewise, for the 2nd fraction, since 9 × 8 = 72,
80/9 = 80 × 8/9 × 8 = 640/72 - Subtract the two like fractions:
21/72 - 640/72 = 21 - 640/72 = -619/72
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/72-80/9 21/72-80/18 63/72-80/9 21/72-80/27 21/72-80/45 21/72-80/63