A researcher wants to know how many security cameras are on average in stores located in...

A researcher wants to know how many security cameras are on average in stores located in a large shopping mall. He randomly selects a sample of 9 stores and finds that on average there are 2.7 security cameras per store with a standard deviation equal to 1.27.

a. Calculate and interpret the 95% confidence interval for the average number of security cameras per store

b. Test the hypothesis that the mean number of cameras per store is 4 at p = 05, 2-tail test. Justify your statistical conclusion.

c. Calculate and interpret the 90% confidence interval for the average number of security cameras per store

Expert Solution

orchestra answered 1 year ago

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