Subtract 20/81 from 4/15
4/15 - 20/81 is 8/405.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 81 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 15 × 27 = 405,
4/15 = 4 × 27/15 × 27 = 108/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
20/81 = 20 × 5/81 × 5 = 100/405 - Subtract the two like fractions:
108/405 - 100/405 = 108 - 100/405 = 8/405
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 8/15-20/81 4/15-40/81 4/30-20/81 12/15-20/81 4/15-60/81 4/45-20/81 20/15-20/81 4/75-20/81 28/15-20/81