10.3

1.

  1. 2.602.

  2. -1.729.

  3. 2.179 and -2.179.

2.

  1. 1.321.

  2. -2.426.

  3. 2.738 and -2.738.

3.

  1. -1.379.

  2. -1.714.

  3. skip

  4. Yes, the researcher will reject the null hypothesis because the test statistic is less than the critical value (left-tailed test).

4.

  1. 2.674.

  2. 1.318.

  3. skip

  4. Yes, the researcher will reject the null hypothesis because the test statistic is greater than the critical value (right-tailed test).

5.

  1. 2.502.

  2. -2.819 and 2.819.

  3. skip

  4. No, the researcher will not reject the null hypothesis because the test statistic falls between the critical values (two-tailed test).

  5. Type answer here.

11.

Ho: u = 67.

H1: u > 67.

  1. This means that the area under the curve to the right of the test statistic is 0.02.

  2. Since the P-value is less than the level of significance (a = 0.05), we reject the null hypothesis and can conclude that people withdraw more money from a PayEase ATM machine.

13.

Ho: u = 22.

H1: u > 22.

  1. n is greater than 200 so it satisfies the requirements.

  2. Critical value: 1.660 Test statistic: 2.176.

  3. Since the test statistic is greater than the critical value, we reject the null hypothesis and can conclude that students who complete the core curriculum are ready for college-level mathematics.

15.

Test statistic: -4.553 Critical value: -2.718 Since the test statistic is less than the critical value (left-tailed test), we reject the null hypothesis and can conclude that alcoholic hippocampi are smaller than 9.02 cubic cm.

17.

Test statistic: 0.813 Critical value: 1.685 Since the test statistic is less than the critical value (right-tailed test), we do not reject the null hypothesis and can state that high-income individuals do not have higher FICO scores than the population.

19.

95% C.I: (37.2, 40.6). This means that the mean age of death-row inmates has not changed.

10.4

1.

  1. 28.87.

  2. 14.041.

  3. 15.247 and 44.81.

3.

  1. 20.496.

  2. 12.338.

  3. Skip but feel free to sketch on a piece of paper for your benefit.

  4. The researcher will not reject the null hypothesis because the value of the test statistic is greater than the critical value (left-tailed test).

13. Feel free to use any method you want. If you use the classical method please report the value of your test statistic and your decision. Likewise if you use the pvalue method please state your pvalue and your decision. Hint: The sample standard deviation (s) is 15.20.

The test statistic is 6.418. The critical value is 3.325 (left-tailed test). So since the value of the test statistic is greater than the critical value, we do not reject the null hypothesis.

15. Feel free to use any method you want. If you use the classical method please report the value of the test statistic and your decision. Likewise if you use the pvalue method please state your pvalue and your decision.

The test statistic is 15.639. The critical value is 15.659 (left-tailed test). So since the test statistic is smaller than the critical value, we reject the null hypothesis and can say that Derrick Rose is more consistent than other shooting guards in the NBA.