Subtract 4/8 from 5/81
5/81 - 4/8 is -71/162.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 8 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 81 × 8 = 648,
5/81 = 5 × 8/81 × 8 = 40/648 - Likewise, for the 2nd fraction, since 8 × 81 = 648,
4/8 = 4 × 81/8 × 81 = 324/648 - Subtract the two like fractions:
40/648 - 324/648 = 40 - 324/648 = -284/648 - After reducing the fraction, the answer is -71/162
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 10/81-4/8 5/81-4/16 15/81-4/8 5/81-12/8 5/81-4/24 25/81-4/8 5/81-20/8 5/81-4/40 35/81-4/8 5/81-28/8 5/81-4/56