Elwin Osbourne, CIO at GFS, Inc., suspects that at least 25% of e-mail messages sent by GFS employees are not business related.A random sample of 300 e-mail messages was selected to test this hypothesis at the 0.01 level of significance.Fifty-four of the messages were not business related.The null hypothesis is ____.
A)$\beta$ = 30
B)n = 300
C)p

Question

Elwin Osbourne, CIO at GFS, Inc., suspects that at least 25% of e-mail messages sent by GFS employees are not business related.A random sample of 300 e-mail messages was selected to test this hypothesis at the 0.01 level of significance.Fifty-four of the messages were not business related.The null hypothesis is ____.
A)$\beta$ = 30
B)n = 300
C)p < 0.25
D)p ≠ 0.25
E)p = 0.25

Quizplus · Accepted Answer

The null hypothesis in hypothesis testing is typically a statement of no effect or no difference. In this context, where the suspicion is that at least 25% of e-mail messages are not business related, the null hypothesis would be that the proportion of non-business related e-mails is equal to 25% (p = 0.25), against which the alternative hypothesis (that the proportion is different from or greater than 25%) is tested.

Elwin Osbourne, CIO at GFS, Inc β\betaβ = 30 B)n = 300 C)p < 0

Elwin Osbourne, CIO at GFS, Inc $\beta$ = 30
B)n = 300
C)p < 0