Actually, why don't I do it in that green color so you see where that came from. So four times three, and then you're going to divide that by the number of ways you can arrange two people. Well, you can arrange two people in two different ways. One's on the left, one's on the right, or the other one's on the left, and the other one's on the right. Or you could also view that as two factorial, which is also equal to two. So we could write this down as two. So this is the number of ways to arrange two people.