you're given a 100 jelly-beans, 50 white and 50 black. You need to set up a game which uses two cups filled with those jelly-beans, you can put a random number of each in each cup, but each cup must have at least one jelly-bean inside. A customer comes up and pick randomly a jelly-bean (it can be white or black), puts it back and then bets money that they can pull out the same color again. As a game provided you want to set it in a way that you have a higher probability of winning the game over a customer. (Hopefully this makes sense)
