Repetitons

Sample Question

If 10 identical papers need to be filed away into any of 4 folders.
How many ways can they be filed away?


This is a fairly simple problem. The numbers we are dealing with are:

After these numbers have been determined, they can be pluged into our forumla:

Solving by standard combination metnods, we get:

So there are 286 ways to file 10 identical papers into 4 folders.