Its a combinatorics problem. Its actually quite subtle. It can be modeled several different ways.
http://en.wikipedia.org/wiki/CombinatoricsThe limiting constraint is that there can be only four quarters.
Given denominations of 1,5,10,25,50, and 100 cents, then there are actually quite a few possible solutions with at least 5 discrete ones. Just playing with a spreadsheet for a few minutes I found several solutions not yet mentioned in this thread.
An edit - I just found a way to generate a lot more solutions. I am up to 20+ now.
Looks like there are around 50 solutions or more. LOL.