Monday, December 12, 2011

Adding fractions with unlike denominators

Steps on how to do adding fractions with unlike denominators.

1) You have two fractions.


2) Now you find the multiples of the two denominators until you find a L.C.M. (lowest common multiple).


4- 4, 8, 12, 16, 20

6- 6, 12, 18, 24, 30

So the L.C.M. is 12.

3) Next you make an equivalent fraction.

How do you get from 4 to 12 and how to you get from 6 to 12?


Always remember whatever you do to the bottom you must do to the top.

4) Now we have two fractions that have the same denominator now we can add them together.


Then you make it into it's simplest form but you can't make 5/12 simpler.

So this is how you add fractions with unlike denominators.


  1. Really good post! It was helpful.

  2. Really great job Jessica! One thing you need to work on you should try not to space things out too much. You should also try to make your pictures bigger, so your classmates can understand better! Other than that, you did a very good job!

  3. Good job Jessica. One thing though... your things are too spaced out. But overall good job Jessica keep it up. This is going to help many people!