Suppose that pizzas can be ordered in four sizes (small, medium, large, and Illini-size), with three crust choices (thin, thick, and Chicago style), four choices of meat (sausage, pepperoni, hamburger, and none) and two types of cheese (regular or double). How many different styles of pizza can be ordered?
How many sizes? 4. So 4 sizes.
How may crust choices? 4. So a total of 4*4=16 styles.
How many choices of meat? 4. So a total of 4*16=64 styles.
How many ...
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