Question

a country is considering raising the speed limit on a road because they claim that the mean speed of vehicles is greater than 45 miles per hour. a random samole of 25 vehicles has a mean speed of 48 miles per hour and a variance of 225 miles. At a 10% significance level, do you have enough evidence to support the countrys claim?

1. what is the claim?

2. what are the hypotheses?

3. what is the sample statistic?

4. what is the test statistic? (show work)

5. what is the critical value? (show work)

6. translate the critical value to a speed in miles per hour, show work:

7. what is alpha?

8. what is the p-value? ( show work)

9. draw a graph labeling the test statistic(s) critical value(s) mean, p-value(s) and critical area(s). label any values on the horizontal axis as both standart random variables and as miles per hour.

10. what is your decision?

11. is it possible that you made an error?

Answer 1