Add 21/12 and 28/27
1st number: 1 9/12, 2nd number: 1 1/27
21/12 + 28/27 is 301/108.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 27 is 108
Next, find the equivalent fraction of both fractional numbers with denominator 108 - For the 1st fraction, since 12 × 9 = 108,
21/12 = 21 × 9/12 × 9 = 189/108 - Likewise, for the 2nd fraction, since 27 × 4 = 108,
28/27 = 28 × 4/27 × 4 = 112/108 - Add the two like fractions:
189/108 + 112/108 = 189 + 112/108 = 301/108 - So, 21/12 + 28/27 = 301/108
In mixed form: 285/108
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/12+28/27 21/12+56/27 21/24+28/27 21/12+28/54 63/12+28/27 21/12+84/27 21/36+28/27 21/12+28/81 21/60+28/27 21/84+28/27