Question

A statistics practitioner is n the process of testing to determine whether there is enough evidence to infer that the population mean is different from 180. She calculated the mean and standard deviation of a sample of 200 observations as x-bar equals 175 and s = 22.

a. Calculate the value of the test statistic required to determine whether there is enough evidence at the 5% significance level. Use Excel to calculate the appropriate p-value as well.
b. Repeat part (a) with s = 45.
c. Repeat part (a) with s = 60.
d. Discuss what happens to the t statistic and the p-value when the standard deviation increases.

Answer 1

The answer and procedures of the exercise are attached in the following image.

Explanation

Please consider the data provided by the exercise. If you have any question please write me back. All the exercises are solved in a single sheet with the formulas indications.