Subtract 81/20 from 4/9
1st number: 4/9, 2nd number: 4 1/20
4/9 - 81/20 is -649/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 9 × 20 = 180,
4/9 = 4 × 20/9 × 20 = 80/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
81/20 = 81 × 9/20 × 9 = 729/180 - Subtract the two like fractions:
80/180 - 729/180 = 80 - 729/180 = -649/180
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 8/9-81/20 4/18-81/20 4/9-81/40 12/9-81/20 4/27-81/20 4/9-81/60 20/9-81/20 4/45-81/20 28/9-81/20 4/63-81/20