Add 12/18 and 21/27
12/18 + 21/27 is 13/9.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 27 is 54
Next, find the equivalent fraction of both fractional numbers with denominator 54 - For the 1st fraction, since 18 × 3 = 54,
12/18 = 12 × 3/18 × 3 = 36/54 - Likewise, for the 2nd fraction, since 27 × 2 = 54,
21/27 = 21 × 2/27 × 2 = 42/54 - Add the two like fractions:
36/54 + 42/54 = 36 + 42/54 = 78/54 - 78/54 simplified gives 13/9
- So, 12/18 + 21/27 = 13/9
In mixed form: 14/9
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/18+21/27 12/18+42/27 12/36+21/27 12/18+21/54 36/18+21/27 12/18+63/27 12/54+21/27 12/18+21/81 60/18+21/27 12/90+21/27 84/18+21/27