# Null Hypothesis and Confidence Interval

Please see the attachment for the fully formatted solution.

The Osborne manufacture makes a soft drink dispensing machine that allows customers to get soft drinks from the machine in a cup with ice. When the machine is running properly, the average number of fluid ounces in the cup should be 14. Periodically the machines need to be tested to make sure that they have not gone out of adjustment. To do this, six cups are filled by the machine and a technician carefully measures the volume in each cup. In one such test, the following data were observed:

a. What would be the correct null hypothesis if the company wishes to test the machine?

b. Calculate the 95% confidence interval. Do you fail to reject the null hypothesis?

© BrainMass Inc. brainmass.com June 4, 2020, 3:14 am ad1c9bdddfhttps://brainmass.com/statistics/confidence-interval/null-hypothesis-confidence-interval-504967

#### Solution Preview

Please check the attachment for the full solution. My answer is written in red.

a) Answer: choose b. Because we want to test whether the average number of fluid ounces in the cup is ...

#### Solution Summary

This solution shows how to formulate a null hypothesis and how to calculate the 95% confidence interval in order to evaluate it.