# Question: Let X the number of living grandparents that a

Let X = the number of living grandparents that a randomly selected adult American has. According to recent General Social Surveys, its probability distribution is approximately P(0) = 0.71, P(1) = 0.15, P(2) = 0.09, P(3) = 0.03, P(4) = 0.02.

a. Does this refer to a discrete or a continuous random variable? Why?

b. Show that the probabilities satisfy the two conditions for a probability distribution.

c. Find the mean of this probability distribution.

a. Does this refer to a discrete or a continuous random variable? Why?

b. Show that the probabilities satisfy the two conditions for a probability distribution.

c. Find the mean of this probability distribution.

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