The average grade of engineering students in SLU is 80. The population standard deviation is 5, and the variable is regularly distributed. A professor claims that his class have a grade that is greater than the average of 80. He chooses 30 students at random and discovers that the mean of their task results is 84. At a 0.05 level, test the claim a ) what is the critical region? b) what is the z- value (or the test value? c.) What is the statistical conclusion?

The average grade of engineering students in SLU is 80. The population standard deviation is 5, and the variable is regularly distributed. A professor claims that his class have a grade that is greater than the average of 80. He chooses 30 students at random and discovers that the mean of their task results is 84. At a 0.05 level, test the claim a ) what is the critical region? b) what is the z- value (or the test value? c.) What is the statistical conclusion?

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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