Question

ou receive a brochure from a large university. The brochure indicates that the mean class size for​ full-time faculty is less than 32 students. You want to test this claim. You randomly select 18 classes taught by​ full-time faculty and determine the class size of each. The results are listed below. Is there enough evidence to support the​ university's claim at

alphaα

​= 0.05?

35	28	29	33	32	40
26	25	29	28	30	36
33	29	27	30	28	25

Hypotheses

What are the null and alternative​ hypothesis?

​(Use the tool pallette for​ symbols.)

nothing

​= nothing

nothing

nothing

nothing

Calculate the Test Statistic and​ P-value.

Test Statistic

nothing

​= nothing

​P-value p​ = nothing

Test result

​P-value  

nothing  

alphaα

A.Reject

Upper H 0H0.

B.Do not reject

Upper H 0H0.

Choose the correct conclusion​ below, with respect to the claim.

A.

​There's enough evidence to suggest the mean class size is less than 32 students.

B.

​There's enough evidence to reject the claim of a mean class size of 32 students.

C.

​There's not enough evidence to reject the claim of a mean class size of 32 students.

D.

​There's not enough evidence to suggest the mean class size is less than 32 students.

Click to select your answer(s).

Answer 1

A B с D E F G H K L 1 35 28 29 33 32 40 mean 30.16667 =AVERAGE(A1:F3) 4.003675 ESTDEV.S(A1:F3) 2 26 25 29 28 30 36 SD 3 33 29 27 30 28 25

HO: u = 32 H1:4<32 Population mean = u = 32 Sample S.D = s=4.003675 Sample size = n =18 Sample mean = 3 = 30.16667 The test statistic is, x- S (30.16667 - 32)/(4.003675/V18) = -1.943 In Degrees of freedom = n-1 = 18 - 1 = 17 P(t < -1.943 ) = 0.0344 [using Excel function T.DIST(-1.943,17,TRUE) ] P-value = P(t< -1.943 ) = 0.0344 Decision Rule : Reject H0 if P-value <a. Here a = 0.1 Conclusion: By decision rule, we reject HO

A.

​There's enough evidence to suggest the mean class size is less than 32 students.