How to add fractions with unlike denominators?

Change the fractions so they have common denominators. For example. If adding 4/8 + 2/3, a common denominator of the two could be 24. Change both fractions to have a denominator of 24. To do this:

(4/8) * (3/3) = 12/24

(2/3) * (8/8) = 16/24

Now that both fractions have denominators of 24, you can simply add the numerators to get your answer. in this case, it would be 28/24

To add fractions with unlike denominators, you need to determine their common denominator.

Say you need to add 3/9 + 7/12.

3/9 and 7/12 have a common denominator of 36.

Here how you solve this:

3/9 = 12/36

7/12 = 21/36

12/36 + 21/36 = 33/36 = 11/12