In 1990, the average annual Medicare spending per enrollee was $3267; in 2003, the average annual Medicare spending per enrollee was $6883. Supposed you hired a consulting firm to take a sample of fifty 2003 Medicare emrollees to further investigate the nature of expenditures. Assume the population standard deviation for 2003 was $2000.

A. Show the sampling distribution of the mean amount of Medicare spending for a sample of fifty 2003 enrollees.

B. What is the probability the sample mean will be within +-$300 of the population means?

C. What is the probability the sample mean will be greater that $7500. If the consulting firm tells you the sample mean for the Medicare enrollees they interviewed was $7500, would you question whether they followed correct simple random sampling procedures.

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