Subtract 9/10 from 28/21
1st number: 1 7/21, 2nd number: 9/10
28/21 - 9/10 is 13/30.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 10 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
28/21 = 28 × 10/21 × 10 = 280/210 - Likewise, for the 2nd fraction, since 10 × 21 = 210,
9/10 = 9 × 21/10 × 21 = 189/210 - Subtract the two like fractions:
280/210 - 189/210 = 280 - 189/210 = 91/210 - After reducing the fraction, the answer is 13/30
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/21-9/10 28/21-18/10 28/42-9/10 28/21-9/20 84/21-9/10 28/21-27/10 28/63-9/10 28/21-9/30 28/21-45/10 28/21-9/50 28/21-63/10 28/21-9/70