A sample of size 20 yields a sample mean of 23.5 and a sample standard deviation of 4.3.

Test H0: Mean 25 at = 0.10. HA: Mean < 25. This is a one-tailed test with lower reject region bounded by a negative critical value.

A.Pvalue 0.068. H0 rejected. Conclude mean < 25

B.Pvalue 0.932. H0 not rejected. Conclude mean 25

C.Pvalue 0.135. H0 not rejected. Conclude mean 25

D.None of the answers are correct.

The results of sampling independent populations:

sample 1 from population 1

mean 80

population variance 3

sample size 25

sample 2 from population 2

mean 81

population variance 2

sample size 50

Note that the population variances are known. Test H0: (population 1 mean - population2 mean) 0 at = 0.05. HA: (population1 mean - population2 mean) > 0. This is a one-tailed test with upper reject region and positive critical value.

A.Pvalue 0.0124. H0 rejected. Concluded difference of means > 0.

B.Pvalue 0.0062. H0 rejected. Concluded difference of means > 0.

C.Pvalue 0.9938. H0 not rejected. Concluded difference of means 0.