Add 12/9 and 21/15
1st number: 1 3/9, 2nd number: 1 6/15
12/9 + 21/15 is 41/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 15 is 45
Next, find the equivalent fraction of both fractional numbers with denominator 45 - For the 1st fraction, since 9 × 5 = 45,
12/9 = 12 × 5/9 × 5 = 60/45 - Likewise, for the 2nd fraction, since 15 × 3 = 45,
21/15 = 21 × 3/15 × 3 = 63/45 - Add the two like fractions:
60/45 + 63/45 = 60 + 63/45 = 123/45 - 123/45 simplified gives 41/15
- So, 12/9 + 21/15 = 41/15
In mixed form: 211/15
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/9+21/15 12/9+42/15 12/18+21/15 12/9+21/30 36/9+21/15 12/9+63/15 12/27+21/15 12/9+21/45 60/9+21/15 12/45+21/15 12/9+21/75 84/9+21/15 12/63+21/15