Subtract 21/20 from 28/35
1st number: 28/35, 2nd number: 1 1/20
28/35 - 21/20 is -1/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 35 × 4 = 140,
28/35 = 28 × 4/35 × 4 = 112/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
21/20 = 21 × 7/20 × 7 = 147/140 - Subtract the two like fractions:
112/140 - 147/140 = 112 - 147/140 = -35/140 - After reducing the fraction, the answer is -1/4
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/35-21/20 28/35-42/20 28/70-21/20 28/35-21/40 84/35-21/20 28/35-63/20 28/35-21/60