# Z test for population mean from researcher

A researcher claims the average American drinks 52 gallons of cola per year with a population standard deviation of 2.0 gallons. We sample 25 random people and find the mean yearly consumption was 49 gallons. Using the significance level a= .10, and assuming a normal distribution what does the evidence conclude?

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Hypothesis Testing (z testing)

A researcher claims the average American drinks 52 gallons of cola per year with a population standard deviation of 2.0 gallons. We sample 25 random people and find the mean yearly consumption was 49 gallons. Using the significance level a= .10, and assuming a ...

#### Solution Summary

The solution provides step by step method for the calculation of z test statistic and p value. Formula for the calculation and Interpretations of the results are also included.