The grade of statistics follows a normal distribution with a mean of 85 and a standard...

The grade of statistics follows a normal distribution with a mean of 85 and a
standard deviation of 10. The instructor adopted a new teaching method this year,
and would like to investigate whether there is an improvement in students’
average grade. Suppose the average grade from a sample of 36 students is 88, can
we conclude that there is an improvement at the 5% significance level?
A. Specify the null and alternative hypotheses.
B. Determine the rejection region.
C. Calculate the test statistics.
D. Make a decision regarding the null hypothesis.
E. Report the conclusion.
F. Describe what a Type I Error would be in this scenario, and what the
consequence might be for the teacher.

Expert Solution

orchestra answered 1 year ago

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