Maxforce, Inc., manufactures racquetball racquets by two different manufacturing processes (A and B). Because the management of this company is interested in estimating the difference between the average time it takes each process to produce a racquet, they select independent samples from each process. The results of the samples are shown below.
Process A Process B
Sample Size 32 35
Sample Mean (in minutes) 43 47
Sample Variance 64 70
a. Develop a 95% confidence interval estimate for the difference between the average time of the two processes.
b. Is there conclusive evidence to prove that one process takes longer than the other? If yes, which process? Explain.