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Question 3 - A Mortgage Company collects data of time taken (in days) to complete mortgage transactions. The following data were obtained for 15 samples of size 5 . Management estimated the process standard deviation to be 4.21 (days) for use in the process capability analysis. The lower and upper specification limits (in days) for the mortgage process times were 5 and 25. (present the details of calculations) a) Is the process in statistical control? (use z=3 in determining the control limits) b) Calculate the process capability index and the process capability ratio values. c) Suppose management would be happy with three-sigma performance. What conclusions is management likely to draw from the capability analysis? d) Can valid conclusions about the process be drawn from the process capability analysis? (hint: the answer to this question depends on your conclusions from part a)