Subtract 21/9 from 45/12
1st number: 3 9/12, 2nd number: 2 3/9
45/12 - 21/9 is 17/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 9 is 36
Next, find the equivalent fraction of both fractional numbers with denominator 36 - For the 1st fraction, since 12 × 3 = 36,
45/12 = 45 × 3/12 × 3 = 135/36 - Likewise, for the 2nd fraction, since 9 × 4 = 36,
21/9 = 21 × 4/9 × 4 = 84/36 - Subtract the two like fractions:
135/36 - 84/36 = 135 - 84/36 = 51/36 - After reducing the fraction, the answer is 17/12
- In mixed form: 15/12
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/12-21/9 45/12-42/9 45/24-21/9 45/12-21/18 45/12-63/9 45/36-21/9 45/12-21/27 45/60-21/9 45/12-21/45 45/84-21/9 45/12-21/63