A random sample of 38 professional baseball players indicated the mean age to be 31.5
years with a standard deviation of 4.4 years. A random sample of 41 professional
basketball players indicated the mean age to 30.3 years with standard deviation 3.8 years.
a. Assume that the preceding data are representative of professional baseball players and
basketball players. Let �! be the population mean age of baseball players and let �" be
the population mean age of basketball players. Find a 75% confidence interval for �!-
�".
b. Examine this confidence interval and explain what it means in this context (if there is
any conclusion)
c. Redo part a and b for a 90% confidence interval. Does your conclusion change?
Explain. (You do not have to redo the assumptions part)