Chapter 8, Problem 4CT

a.

To determine

To identify: The claim and state $H_0$ and $H_a$.

b.

To determine

Whether the hypothesis test is left-tailed, right-tailed or two-tailed.

To check: Whether to use z-test or t-test.

c.

To determine

To find: The critical value and rejection region with $\alpha =0.01$.

d.

To determine

To find: The standardized test statistic t.

e.

To determine

To decide: Whether to reject or fail to reject the null hypothesis at a level of significance of $\alpha =0.01$.

f.

To determine

To interpret: The decision in the context of the original claim.