A Single Population Mean Using the Student's t-Distribution · Exercise 27

Suppose that a committee is studying whether there is wasted time in our judicial system. It is interested in the mean amount of time individuals waste at the courthouse waiting to be called for jury duty. The committee randomly surveyed 81 people who recently served as jurors. The sample mean wait time was 8 hr, with a sample standard deviation of 4 hr.

(a) (a) $\bar{x}$ = __________
(b) $s_x$ = __________
(c) n = __________
(d) n – 1 = __________
(b) Define the random variables $X$ and $\bar{X}$ in words.
(c) Which distribution should you use for this problem? Explain your choice.
(d) Construct a 95 percent confidence interval for the population mean time wasted.
(a) State the confidence interval.
(b) Sketch the graph.
(c) Calculate the error bound.
(e) Explain in a complete sentence what the confidence interval means.

Its source prints no answer for this problem, so there's nothing to check against.

OpenStax, Statistics · §8.2 A Single Population Mean Using the Student's t-Distribution · Exercise 27