Subtract 21/20 from 90/28
1st number: 3 6/28, 2nd number: 1 1/20
90/28 - 21/20 is 303/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 28 × 5 = 140,
90/28 = 90 × 5/28 × 5 = 450/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
21/20 = 21 × 7/20 × 7 = 147/140 - Subtract the two like fractions:
450/140 - 147/140 = 450 - 147/140 = 303/140 - In mixed form: 223/140
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/28-42/20 90/56-21/20 90/28-21/40 90/28-63/20 90/84-21/20 90/28-21/60