Subtract 75/20 from 28/21
1st number: 1 7/21, 2nd number: 3 15/20
28/21 - 75/20 is -29/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
28/21 = 28 × 20/21 × 20 = 560/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
75/20 = 75 × 21/20 × 21 = 1575/420 - Subtract the two like fractions:
560/420 - 1575/420 = 560 - 1575/420 = -1015/420 - After reducing the fraction, the answer is -29/12
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/21-75/20 28/42-75/20 28/21-75/40 84/21-75/20 28/63-75/20 28/21-75/60