Hi all, my fractions are not great to be honest but here is my question.

Using addition, solve for a and b:

So I find a common multiple of b, I choose to use 24.

Now I go ahead and do the addition:

I'm left with:

Is this correct so far? If so then I plug the answer back into the equation and get:

I only know from using a website that

My question is I just don't know how to go about finding the correct fraction, is there a simple method?