Subtract 20/81 from 4/8
4/8 - 20/81 is 41/162.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 81 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 8 × 81 = 648,
4/8 = 4 × 81/8 × 81 = 324/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
20/81 = 20 × 8/81 × 8 = 160/648 - Subtract the two like fractions:
324/648 - 160/648 = 324 - 160/648 = 164/648 - After reducing the fraction, the answer is 41/162
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 4/8-40/81 4/16-20/81 12/8-20/81 4/8-60/81 4/24-20/81 20/8-20/81 4/40-20/81 28/8-20/81 4/56-20/81