#1) Ron Wood, an MBA student, has joined Precision Manufacturers as a Quality Analyst. One of his first assignments is to introduce quality initiatives in the production of shafts used in engine lathes. Attached to the machine producing shafts is an X-bar chart and R chart for monitoring diameter of shafts. The present control chart has Center Line (mean X) = 2.5 inches, and three standard deviation control limits of UCL = 2.518 inches and LCL = 2.482 inches. In his enthusiasm to reduce inspection costs, he decides to reduce the current sample size of 20 units to 10 units. Compute the revised control limits for X-bar chart and R-chart for the new sample size of 10 units. (9 points) #2) Twenty samples were taken from a cable manufacturing machine while it was being operated under closely controlled conditions. The number of defects per 100 meters for the samples is recorded below: 4, 4, 5, 3, 6, 2, 2, 4, 5, 3, 4, 2, 3, 2, 4, 5, 5, 7, 5, 3. Determine 3 control limits (use appropriate chart) for monitoring defects of the process. (4 points) #3) A State university is interested in monitoring and controlling the number of students dropping every semester. The average academic drops in every semester is expected to be around 4 percent. Information about last 4 semester is as follows: Sample # Sample size Number of Drops 1 200 12 2 120 12 3 200 10 4 150 14 Set up appropriate 3-standard deviation control limits for the problem. Are above samples in control? Explain. (6 points)

#4) A distributor of electrical switches is interested in implementing a total quality program. Following data is collected about the organization's receiving process. Date Packing slips Number of Errors 21 January 73 7 22 January 79 13 23 January 87 15 24 January 84 3 25 January 92 23 The number of packing slips is expected to be varying each day. Set up appropriate 3- standard deviation control limits for the problem. Is the process in control during the during the (above) dates? Explain. (6 points)