WoW Mathematics: My Large Brown Sack

To help find items easily, players often organise them in their bags in a certain way. It might be interesting to know just how many ways those items can be arranged, and what happens of those arrangements are restricted in some way.

Permutations are very useful in this process. It is a special case of the fundamental counting technique where an object, once picked, cannot be picked again, and so the available pool of objects decreases by one each time. Consider a certain 10-slot bag, the Large Brown Sack...