Subtract 21/81 from 6/28
6/28 - 21/81 is -17/378.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 81 is 2268
Next, find the equivalent fraction of both fractional numbers with denominator 2268 - For the 1st fraction, since 28 × 81 = 2268,
6/28 = 6 × 81/28 × 81 = 486/2268 - Likewise, for the 2nd fraction, since 81 × 28 = 2268,
21/81 = 21 × 28/81 × 28 = 588/2268 - Subtract the two like fractions:
486/2268 - 588/2268 = 486 - 588/2268 = -102/2268 - After reducing the fraction, the answer is -17/378
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 12/28-21/81 6/28-42/81 6/56-21/81 18/28-21/81 6/28-63/81 6/84-21/81 30/28-21/81 42/28-21/81