math
posted by cole .
i have 5 coins,a penny,nickel,dime,quarter and loonie. how many different amounts of money can i pay using any combination of the coins?

I can use the penny in two ways, that is, either use it or not use it.
The same goes for the other 4 coins
So the number of ways is
2x2x2x2x2 = 32
but that includes not using any coins, which would not be an "amount of money"
so the number of ways is 31