Q 21

Question 21

Statistics professor Dr. Stat claimed his pulse rate at the peak of an exercise program was lower than the mean pulse rate of statistics students. Dr. Stat's pulse rate was measured to be 60.0 bpm. His 20 students had a mean pulse rate of 74.4 bpm with a standard deviation of 10.0 bpm. What critical value you should use to test Dr. Stat's claim that statistics students have a mean pulse rate greater than 60.0 bpm at a 0.01 significance level?

Select one:

a. 2.325

b. 2.528

c. 2.539

d. 2.845

e. 2.861

Q 22

Question 22

Which of the following isnottrue about ap-value?

Select one:

a. Ap-value is the likelihood that a sample such as the one obtained will occur when H0is actually true.

b. Ap-value is the probability of obtaining a value of the sample test statistic that is at least as extreme as the one found from the sample data, assuming H0is false.

c. Smallp-values indicate that the sample results are unusual.

d. Largep-values indicate that there is not a significant difference from H0.

e. Ap-value will be smaller than the significance level when the test statistic falls within the critical region.

Q 24

Question 24

From the National Health and Nutrition Examination Survey, a sample of 50 nonsmokers exposed to environmental tobacco smoke (ETS) have a mean serum cotinine level of 4.10 ng/ml with standard deviation 10.21 ng/ml, and a sample of 50 nonsmokers not exposed to ETS have a mean serum cotinine level of 0.41 ng/ml with standard deviation 1.21 ng/ml. Using these data, you need to construct a 95% confidence interval estimate of the difference between the mean serum cotinine level of exposed nonsmokers and unexposed nonsmokers. Assuming that the population variances are known to be equal to the two sample variances, what value should you use for the margin of error?

Select one:

a. 0.17

b. 1.45

c. 1.96

d. 2.11

e. 2.85

Q 25

Question 25

The Federal Trade Commission provided measured nicotine contents (in mg) of randomly selected king-size cigarettes. A random sample of 21 filtered king-size cigarettes has a mean nicotine content of 0.94 mg with standard deviation 0.31 mg. A random sample of 8 nonfiltered king-size cigarettes has a mean nicotine content of 1.65 mg with standard deviation 0.16 mg. Assuming equal variances between the two populations of cigarettes, you need to test the claim that the mean amount of nicotine in filtered king-size cigarettes is equal to the mean amount of nicotine in nonfiltered king-size cigarettes at a 0.05 significance level. What should you use for the critical values?

Select one:

a. 1.65

b. 1.96

c. 2.05

d. 3.84

e. 6.12