Life Viewed Through an Amber Focus

I just wanted to give a big thank you to all you marvelous f-listers who helped me with that math problem yesterday.  I was able to explain it to T in a way that he could understand it.  He at least gets it.  I don't know what I ever would have done before the internet!

I have a guess and check story problem I am trying to figure out so I can help my son figure it out and all I am managing to do at the moment is bang my head against the wall.  The problem is this:

Russell had just served up 55 cones, some single scoops, some double scoops, and some triple scoops.  If he served up a total of 103 scoops, how many of the cones were single scoops, how many were double scoops, and how many were triple scoops?

Usually I figure out guess and checks algebraically, but I can't do that here because there is not enough information and I've gone through two pieces of scrap paper trying to figure it out otherwise.  We didn't have bloody problems like this when I was in the fifth grade!