Subtract 2/3 from 21/18
1st number: 1 3/18, 2nd number: 2/3
21/18 - 2/3 is 1/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 3 is 18
Next, find the equivalent fraction of both fractional numbers with denominator 18 - For the 1st fraction, since 18 × 1 = 18,
21/18 = 21 × 1/18 × 1 = 21/18 - Likewise, for the 2nd fraction, since 3 × 6 = 18,
2/3 = 2 × 6/3 × 6 = 12/18 - Subtract the two like fractions:
21/18 - 12/18 = 21 - 12/18 = 9/18 - After reducing the fraction, the answer is 1/2
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/18-2/3 21/18-4/3 21/36-2/3 21/18-2/6 63/18-2/3 21/18-6/3 21/54-2/3 21/18-2/9 21/18-10/3 21/90-2/3 21/18-2/15 21/18-14/3 21/18-2/21