Oxbridge University is contemplating a policy under which they would pay employees to not bring their vehicles to campus. Instead of paying an annual fee for on-campus parking, employees would receive a rebate from the university, provided that they found alternative means of getting back and forth to work. Since this idea is unusual, Oxbridge University is contemplating a policy under which they would pay employees to not bring their vehicles to campus. Instead of paying an annual fee for on-campus parking, employees would receive a rebate from the university, provided that they found alternative means of getting back and forth to work. Since this idea is the university wants to estimate the proportion of its employees who would sign up. When the option was offered to a random sample of 40 employees, 5 signed up.
a. What is the estimated proportion that will sign up? What is the estimated standard deviation of the proportion that will sign up?
b. What is a 95 percent confidence interval for the proportion that will sign up?
c. How large a sample size is required to obtain a 95 percent confidence interval of ± 0:05?