Subtract 21/18 from 18/12
1st number: 1 6/12, 2nd number: 1 3/18
18/12 - 21/18 is 1/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 18 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 12 × 3 = 36,
18/12 = 18 × 3/12 × 3 = 54/36 - Likewise, for the 2nd fraction, since 18 × 2 = 36,
21/18 = 21 × 2/18 × 2 = 42/36 - Subtract the two like fractions:
54/36 - 42/36 = 54 - 42/36 = 12/36 - After reducing the fraction, the answer is 1/3
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/12-21/18 18/12-42/18 18/24-21/18 18/12-21/36 54/12-21/18 18/12-63/18 18/36-21/18 18/12-21/54 90/12-21/18 18/60-21/18 18/12-21/90 18/84-21/18