Subtract 9/28 from 9/21
9/21 - 9/28 is 3/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
9/21 = 9 × 4/21 × 4 = 36/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
9/28 = 9 × 3/28 × 3 = 27/84 - Subtract the two like fractions:
36/84 - 27/84 = 36 - 27/84 = 9/84 - After reducing the fraction, the answer is 3/28
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 18/21-9/28 9/21-18/28 9/42-9/28 9/21-9/56 27/21-9/28 9/21-27/28 9/63-9/28 9/21-9/84 45/21-9/28 9/21-45/28 63/21-9/28 9/21-63/28