Question

A professional employee in a large corporation receives an average of µ = 41.7 e-mails per...

A professional employee in a large corporation receives an average of µ = 41.7 e-mails per day. An anti-spam protection program was installed in the company's server and one month later a random sample of 45 employees showed that they were receiving an average of ?̅= 36.2 e-mails per day. Assume that ơ = 18.45. Use a 5% level of significance to test whether there has been a change (either way) in the average number of emails received per day per employee.

a.) What is α? State the null and alternate hypotheses. Will you use a left-tailed, right-tailed, or two-tailed test?

αα =

H0H0: μμ =

H1H1: μμ Select an answer < not = >  

The test is a Select an answer two-tailed right-tailed left-tailed  test

b.) Identify the Sampling Distribution you will use. What is the value of the test statistic?

The best sampling distribution to use is the Select an answer Normal Student's t  distribution.

The test statistic (z or t value) is =

c.) Find or estimate the P-value for the test.

The p-value is =

d.) Conclude the test.

Based on this we will Select an answer Reject Fail to reject  the null hypothesis.

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