Subtract 21/40 from 20/60
20/60 - 21/40 is -23/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 40 is 120
Next, find the equivalent fraction of both fractional numbers with denominator 120 - For the 1st fraction, since 60 × 2 = 120,
20/60 = 20 × 2/60 × 2 = 40/120 - Likewise, for the 2nd fraction, since 40 × 3 = 120,
21/40 = 21 × 3/40 × 3 = 63/120 - Subtract the two like fractions:
40/120 - 63/120 = 40 - 63/120 = -23/120
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/60-21/40 20/60-42/40 20/60-21/80 20/60-63/40