Subtract 1/8 from 7/81
7/81 - 1/8 is -25/648.
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,
7/81 = 7 × 8/81 × 8 = 56/648 - Likewise, for the 2nd fraction, since 8 × 81 = 648,
1/8 = 1 × 81/8 × 81 = 81/648 - Subtract the two like fractions:
56/648 - 81/648 = 56 - 81/648 = -25/648
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 14/81-1/8 7/81-2/8 7/81-1/16 21/81-1/8 7/81-3/8 7/81-1/24 35/81-1/8 7/81-5/8 7/81-1/40 49/81-1/8 7/81-7/8 7/81-1/56