Add 21/12 and 45/9
1st number: 1 9/12, 2nd number: 5 0/9
21/12 + 45/9 is 27/4.
Steps for adding 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,
21/12 = 21 × 3/12 × 3 = 63/36 - Likewise, for the 2nd fraction, since 9 × 4 = 36,
45/9 = 45 × 4/9 × 4 = 180/36 - Add the two like fractions:
63/36 + 180/36 = 63 + 180/36 = 243/36 - 243/36 simplified gives 27/4
- So, 21/12 + 45/9 = 27/4
In mixed form: 63/4
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/12+45/9 21/12+90/9 21/24+45/9 21/12+45/18 63/12+45/9 21/36+45/9 21/12+45/27 21/60+45/9 21/84+45/9 21/12+45/63