Thanksgiving is almost here. As you gather around the table this Thursday and see platters of turkey, mashed potatoes, stuffing, green bean cassarole and cranberry sauce, you may wonder, "How many different kinds of meals are possible?" After all, a plate of just turkey and mashed potatoes is different than one with every type of food being served.
This kind of question is best answered by thinking of it as a combination. Combinations are one way of counting things, and this idea is used with certain types of probability applications. To calculate a combination, you need to know a thing or two about factorials.
There's still plenty of time before Thanksgiving to practice calculating combinations and then check your answers. Then you will be all set to figure out how many types of plates are possible at dinner. But don't try to eat all of them.