Use the Following to Answer Questions

question 23

Multiple Choice

Use the following to answer questions :
A sample of 31 male students and another sample of 33 female students from the same college produced mean G.P.As of 2.66 for the males and 2.89 for the females.Suppose that the standard deviations of the G.P.As are 0.71 for the males and 0.63 for the females.The null hypothesis is that the mean G.P.A's are the same for males and females,while the alternative hypothesis is that the mean G.P.A for males is less than the mean G.P.A for females.
-The significance level for the test is 2.5%.What is the critical value of z?

• A)-2.58
• B)-1.96
• C)-2.33
• D)-1.65