Question

A class survey in a large class for first-year college students asked, "About how many minutes do you study on a typical weeknight?" The mean response of the 272 students was x¯¯¯x¯ = 148 minutes. Suppose that we know that the studey time follows a Normal distribution with standard deviation σσ = 65 minutes in the population of all first-year students at this university. Regard these students as an SRS from the population of all first-year students at this university. Does the study give good evidence that students claim to study more than 2 hours per night on the average?

(a) State null and alternative hypotheses in terms of the mean study time in minutes for the population.
(b) What is the value of the test statistic zz?
(c) Can you conclude that students do claim to study more than two hours per weeknight on the average?

(a) H0H0:  HaHa:  (Type in "mu" as the substitute for μμ and "!=" for ≠≠.)
(b) zz:  
(c) Conclusion:  (Answer with "Yes/Y" or "No/N".)

Answer 1

This is the right tailed test .

The null and alternative hypothesis is

H₀ : = 120

H_a : > 120

Test statistic = z

= ( - ) /    / n

= (148 - 120) / 65 / 272

Test statistic = 7.10

P-value = 0.000

P-value <

Reject the null hypothesis .

Yes