Subtract 7/81 from 28/30
28/30 - 7/81 is 343/405.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 30 × 27 = 810,
28/30 = 28 × 27/30 × 27 = 756/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
7/81 = 7 × 10/81 × 10 = 70/810 - Subtract the two like fractions:
756/810 - 70/810 = 756 - 70/810 = 686/810 - After reducing the fraction, the answer is 343/405
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/30-7/81 28/30-14/81 28/60-7/81 84/30-7/81 28/30-21/81 28/90-7/81 28/30-35/81 28/30-49/81