Add 12/9 and 27/21
1st number: 1 3/9, 2nd number: 1 6/21
12/9 + 27/21 is 55/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 9 × 7 = 63,
12/9 = 12 × 7/9 × 7 = 84/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
27/21 = 27 × 3/21 × 3 = 81/63 - Add the two like fractions:
84/63 + 81/63 = 84 + 81/63 = 165/63 - 165/63 simplified gives 55/21
- So, 12/9 + 27/21 = 55/21
In mixed form: 213/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/9+27/21 12/9+54/21 12/18+27/21 12/9+27/42 36/9+27/21 12/9+81/21 12/27+27/21 12/9+27/63 60/9+27/21 12/45+27/21 84/9+27/21 12/63+27/21