SOLUTION: Within a university, students were randomly assigned to one of the two statistics instructors - instructor A and instructor B. After the assignment instructor a had 30 students and

Question 1081558: Within a university, students were randomly assigned to one of the two statistics instructors - instructor A and instructor B. After the assignment instructor a had 30 students and instructor B had 25 students. At the end of the semester, each class took the same standardized test. Instructor A students had an average test score of 78 with a standard deviation of 10; and Instructor B student had an average score of 85 with a standard deviation of 15. Test the hypothesis that instructor A and B are equally effective instructors. Use a 0.10 level of significance.
Thank You. Please help me for my exam.
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Within a university, students were randomly assigned to one of the two statistics instructors - instructor A and instructor B. After the assignment instructor a had 30 students and instructor B had 25 students. At the end of the semester, each class took the same standardized test. Instructor A students had an average test score of 78 with a standard deviation of 10; and Instructor B student had an average score of 85 with a standard deviation of 15. Test the hypothesis that instructor A and B are equally effective instructors. Use a 0.10 level of significance.
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Ho: uA - uB = 0 (claim)
Ha: uA - uB # 0
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test statistic:: z(78-85) = (-7/sqrt[{10^2/30) + (15^2/25)] = -1.99
---------------0.
P-value = 2*P(-100< z < -1.99) = 2*normalcdf(-100,-1.99) = 0.047
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Conclusion:: Since the P-value is less than 5%, reject Ho.
Conclusion:: The test results do not support the claim that
the instructors are equally capable at the 5% level of significance.
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Cheers,
Stan H.
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