Two machines are used for filling plastic bottles with a net volume of 16.0 ounces. The

Chapter 10, Problem 10-4

(choose chapter or problem)

Two machines are used for filling plastic bottles with a net volume of 16.0 ounces. The fill volume can be assumed normal, with standard deviation 1 0.020 and 2 0.025 ounces. A member of the quality engineering staff suspects that both machines fill to the same mean net volume, whether or not this volume is 16.0 ounces. A random sample of 10 bottles is taken from the output of each machine. Machine 1 Machine 2 16.03 16.01 16.02 16.03 16.04 15.96 15.97 16.04 16.05 15.98 15.96 16.02 16.05 16.02 16.01 16.01 16.02 15.99 15.99 16.00 (a) Do you think the engineer is correct? Use 0.05. What is the P-value for this test? (b) Calculate a 95% confidence interval on the difference in means. Provide a practical interpretation of this interval. (c) What is the power of the test in part (a) for a true difference in means of 0.04? (d) Assuming equal sample sizes, what sample size should be used to assure that 0.05 if the true difference in means is 0.04? Assume that 0.05