The operations manager at Gnyxl, Inc. is attempting to determine if there is a difference between two different job sequencing rules (job sequencing is the determination of what product the worker should work on first). He has gathered the following information on the times, in seconds, that it takes to change from one product to the next. If he is satisfied with a 10% significance level, set up the hypotheses used to test this assertion, perform the test and interpret the results. Assume that the variances are equal. Construct a 90% confidence interval for the difference between the changeover times.
Rule 1
8.8 9.6 8.4 9.0 8.3 9.2 9.0 8.7 8.5 9.4
Rule 2
9.2 9.4 8.9 9.6 9.7 8.4 8.8 8.9 9.0 9.7 9.2 9.0