Add 12/45 and 21/18
1st number: 12/45, 2nd number: 1 3/18
12/45 + 21/18 is 43/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 45 × 2 = 90,
12/45 = 12 × 2/45 × 2 = 24/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
21/18 = 21 × 5/18 × 5 = 105/90 - Add the two like fractions:
24/90 + 105/90 = 24 + 105/90 = 129/90 - 129/90 simplified gives 43/30
- So, 12/45 + 21/18 = 43/30
In mixed form: 113/30
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/45+21/18 12/45+42/18 12/90+21/18 12/45+21/36 36/45+21/18 12/45+63/18 12/45+21/54 60/45+21/18 12/45+21/90 84/45+21/18