Can someone please check this generating function

Hi

Please have a look at the link.

http://i50.tinypic.com/mm4uj7.jpg

I have attempted to answer a distribution problem by a generating function. Please tell me if it is correct and if its not HOW I can correct it. MANY THANKS

Very close!

I believe that you should have x^23 instead of x^22 when you perform the factoring (that affects the answer a little bit). Otherwise, the procedure looks fine.

I hope this helps!