This video instructs on how to find the sum of fractions that have the same denominator. In order to do this, all that needs to be done is to add the different numerators together, then put the sum of those numbers over the common denominator. The example used is 2/9 + 1/9 + 5/9. The first step is to add the numerators which gives you 2 + 1 + 5/9. Then simplify the fraction adding 2 + 1 + 5 which equals 8. That is your numerator. The denominator does not change because it is common, so the final result is 8/9.