Subtract 80/21 from 3/28
1st number: 3/28, 2nd number: 3 17/21
3/28 - 80/21 is -311/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
3/28 = 3 × 3/28 × 3 = 9/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
80/21 = 80 × 4/21 × 4 = 320/84 - Subtract the two like fractions:
9/84 - 320/84 = 9 - 320/84 = -311/84
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/28-80/21 3/56-80/21 3/28-80/42 9/28-80/21 3/84-80/21 3/28-80/63 15/28-80/21 21/28-80/21