1.     In Sibling.xls you will find the probability distribution for X = number of siblings of a
        WCU student from the data collected from my stat classes this semester. We will
        assume that these data form a random sample of all WCU students, so that this
        information is representative of the population. (The idea for this random variable
        originated with Rhonda C. Magel in Increasing Student Participation in Large
        Introductory Statistics Classes, The American Statistician, Feb., 1996, Vol. 50,
        No. 1, p. 52.)

2.     What is the probability a randomly selected WCU student has only one
        sibling?

3.     What is the probability a randomly selected WCU student has at most one
        sibling?

4.     Use Excel to compute the expected value of X. Interpret the result. What types
        of businesses might be interested in your computed value?

5.     Use Excel to compute the standard deviation of X. Interpret this value. How
        would this piece of information enhance the use of the businesses you named in
        Question 4?

6.     Suppose the WCU Bookstore wants to order greeting cards for a special
        occasion, such as Sibling Day. It wants to avoid unsold cards. Assume there are
        6500 WCU students currently. Use the information in the probability distribution
        and your answers to the above questions to recommend a number of sibling
        cards to order. Write a memo to include your recommendation and an
        explanation.

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