Subtract 9/18 from 21/20
1st number: 1 1/20, 2nd number: 9/18
21/20 - 9/18 is 11/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 18 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
21/20 = 21 × 9/20 × 9 = 189/180 - Likewise, for the 2nd fraction, since 18 × 10 = 180,
9/18 = 9 × 10/18 × 10 = 90/180 - Subtract the two like fractions:
189/180 - 90/180 = 189 - 90/180 = 99/180 - After reducing the fraction, the answer is 11/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/20-9/18 21/40-9/18 21/20-9/36 63/20-9/18 21/20-27/18 21/60-9/18 21/20-9/54 21/20-45/18 21/20-9/90 21/20-63/18