Subtract 81/40 from 21/10
1st number: 2 1/10, 2nd number: 2 1/40
21/10 - 81/40 is 3/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 40 is 40
Next, find the equivalent fraction of both fractional numbers with denominator 40 - For the 1st fraction, since 10 × 4 = 40,
21/10 = 21 × 4/10 × 4 = 84/40 - Likewise, for the 2nd fraction, since 40 × 1 = 40,
81/40 = 81 × 1/40 × 1 = 81/40 - Subtract the two like fractions:
84/40 - 81/40 = 84 - 81/40 = 3/40
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/10-81/40 21/20-81/40 21/10-81/80 63/10-81/40 21/30-81/40 21/50-81/40 21/70-81/40