Subtract 21/30 from 2/5
2/5 - 21/30 is -3/10.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 30 is 30
Next, find the equivalent fraction of both fractional numbers with denominator 30 - For the 1st fraction, since 5 × 6 = 30,
2/5 = 2 × 6/5 × 6 = 12/30 - Likewise, for the 2nd fraction, since 30 × 1 = 30,
21/30 = 21 × 1/30 × 1 = 21/30 - Subtract the two like fractions:
12/30 - 21/30 = 12 - 21/30 = -9/30 - After reducing the fraction, the answer is -3/10
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 4/5-21/30 2/5-42/30 2/10-21/30 2/5-21/60 6/5-21/30 2/5-63/30 2/15-21/30 2/5-21/90 10/5-21/30 2/25-21/30 14/5-21/30 2/35-21/30