A textbook company states that the average time a student needs to take a quiz from its book is 30 minutes with a standard deviation of 3 minutes. A teacher using the book is not sure that this is correct for her classes and wants to check. She collects data on 10 random students and finds that the average time to take the quiz was only 25 minutes. As a result, the teacher performs a two-tailed hypothesis test with a significance level of 5%. Which conclusion is valid based on the results of the test?
4 answers
Have you considered trying to do any of these?
In general you might find this handy:
http://davidmlane.com/hyperstat/z_table.html
http://davidmlane.com/hyperstat/z_table.html
What conclusions are listed?
Her students, on average, do not take 30 minutes on the quiz, contrary to what the textbook company stated.