Subtract 24/27 from 21/28
21/28 - 24/27 is -5/36.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 27 is 756
Next, find the equivalent fraction of both fractional numbers with denominator 756 - For the 1st fraction, since 28 × 27 = 756,
21/28 = 21 × 27/28 × 27 = 567/756 - Likewise, for the 2nd fraction, since 27 × 28 = 756,
24/27 = 24 × 28/27 × 28 = 672/756 - Subtract the two like fractions:
567/756 - 672/756 = 567 - 672/756 = -105/756 - After reducing the fraction, the answer is -5/36
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/28-24/27 21/28-48/27 21/56-24/27 21/28-24/54 63/28-24/27 21/28-72/27 21/84-24/27 21/28-24/81