Subtract 21/80 from 1/20
1/20 - 21/80 is -17/80.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 80 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 20 × 4 = 80,
1/20 = 1 × 4/20 × 4 = 4/80 - Likewise, for the 2nd fraction, since 80 × 1 = 80,
21/80 = 21 × 1/80 × 1 = 21/80 - Subtract the two like fractions:
4/80 - 21/80 = 4 - 21/80 = -17/80
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 2/20-21/80 1/20-42/80 1/40-21/80 3/20-21/80 1/20-63/80 1/60-21/80 5/20-21/80 7/20-21/80