A simple random sample of 70 customers is taken froma customer information file and the average...

A simple random sample of 70 customers is taken froma customer information file and the average age is 36. The population standard deviation o is unknown. Instead the sample standard deviation s is also calculated from the sample and is found to be 4.5. 2. Test the hypothesis that the population mean age is greater than 33 using the critical value approach and a 0.05 level of significance. а. Test the hypothesis that the population mean age is less than 38 using the p- value approach and a 0.05 level of significance. b. Test the hypothesis that the population mean age is different from 32 using the p-value approach and a 0.05 level of significance. с.

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milcah answered 3 months ago

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