Question

4 pts X Ons wit in ap The average GPA score for students at a university was 3.75. rive years later, a professor wants to perform a hypothesis test to determine whether the average GPA score of students at the university has changed. He picks a random sample of 50 students and obtains their mean GPA score, which is 3.10. The population standard deviation is known as 1.15. Test whether the claim that the average GPA score at the university has dropped from 3.75 is supported or not supported. At 58 level of significance, the rejection region of the test is Jake z -1.96 O I O z> 1.645 Oz< -1.645 O z> 1.96

Answer 1

Solution or Hot M = 3.45 VS Hi MC3.15 where M is the mean GipA score fora students. sample size is 50. o=1:15 Test statistic for this test- is ZB= Ho 01550 N(011). from central limit theorem considering size is Critical Region: Zse sample ITA Where Cis chosen large in such a way that PLZ*<< | Ho] = 0.05 > PC X-3.75 50.05 A 1151 Tho <c] to NIR we know if I~ NCO then P(Z <-1.645) a Plot = 5/100 - we get, com A c = omparing and B -1.645 Hope za is the z-score hat denote critical region is newnitten 1 ZC-1645) Ane (c) then as