A simple random sample of 20 customers is taken from a customer information file and the...

A simple random sample of 20 customers is taken from a customer information file and the average age is 27. The sample standard deviation s is found to be 5. (5 marks)
1. Test the hypothesis that the population mean age is less than 29 using the critical value approach and a 0.10 level of significance.
1. Test the hypothesis that the population mean age is different from 30 using the 0.05 level of significance.

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orchestra answered 1 year ago

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