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Video transcript

in the previous video and exercise we saw how a table is a great way to keep track of a lot of different kinds of robots where each robot is made up of one head and one body let's call each of those different robots a combination you experience combinations all the time for instance when you wake up in the morning and you pick out a top and some bottoms to wear that's a combination notice that since each cell in the table corresponds to a different combination we just need to count the number of cells but we don't have to count one by one that's because the number of cells in a table is just the number of rows times the number of columns so with two heads and three bodies we have two times three or six different combinations and with three heads and four bodies we have 3 times 4 or 12 different combinations the next exercise will give you a chance to practice with other combinations