11.9 Practice 3: test of a single variance

Is the traveler disputing the claim about the average or about the variance?

A sample standard deviation of 15 minutes is the same as a sample variance of __________ minutes.

Is this a right-tailed, left-tailed, or two-tailed test?

$H_o:$

Degrees of freedom =

${\text{Chi}}^2$ test statistic =

p-value =

Graph the situation. Label and scale the horizontal axis. Mark the mean and test statistic. Shade the p-value.

Let $\alpha =0\text{.}\text{05}$

Decision:

Conclusion (write out in a complete sentence):

How did you know to test the variance instead of the mean?

If an additional test were done on the claim of the average delay, which distribution would you use?

If an additional test was done on the claim of the average delay, but 45 flights were surveyed, which distribution would you use?