Subtract 1/81 from 2/21
2/21 - 1/81 is 47/567.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 21 × 27 = 567,
2/21 = 2 × 27/21 × 27 = 54/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
1/81 = 1 × 7/81 × 7 = 7/567 - Subtract the two like fractions:
54/567 - 7/567 = 54 - 7/567 = 47/567
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 4/21-1/81 2/21-2/81 2/42-1/81 6/21-1/81 2/21-3/81 2/63-1/81 10/21-1/81 2/21-5/81 14/21-1/81 2/21-7/81