A researcher is interested in the mean amount of time it takespeople to complete a personality questionnaire. He selects 40people at random and calculates the mean amount of time to be 20.4min with a variance of 17.64 min2 .
a) Define the parameter of interest.
b) Define the random variable of interest.
c) Name the distribution required to calculate confidenceintervals. (Check the relevant criteria.)
d) Construct a 98% confidence interval for the true mean amountof time.
e) Interpret your confidence interval.
