A process at Printwright, Inc.’s largest facility is used to make plastic gears for a computer printer. The data found in the worksheet Prob. 9-15 were gathered by a quality analyst. The gears were designed to be 3.57 ` 0.05 centimeters (cm) in diameter. Construct a histogram of the data. What can you observe about the shape of the dis- tribution? What would you recommend to the production manager based on your analysis?

The accounts receivable department at Rick WingManufacturing has been having difficulty getting customers topay the full amount of their bills. Many customers complainthat the bills are not correct and do not reflect the materials thatarrived at their receiving docks. The department has decided toimplement SPC in its billing process. To set up control charts, 10samples of 50 bills each were taken over a month’s time and theitems on the bills checked against the bill of lading sent by thecompany’s shipping department to determine the number of billsthat were not correct. The results were: SAMPLENO. NO. OFINCORRECTBILLS SAMPLENO. NO. OFINCORRECTBILLS1 6 6 52 5 7 33 11 8 44 4 9 75 0 10 2a) Determine the value of p -bar, the mean fraction defective.Then determine the control limits for the p -chart using a99.73% confidence level (3 standard deviations). Has thisprocess been in control? If not, which samples were out ofcontrol?b) How might you use the quality tools discussed in Chapter 6to…

A shirt manufacturer buys cloth by the 100-yard roll from a supplier. For setting up a control chart to manage the irregularities (e.g., loose threads and tears), the following data were collected from a sample provided by the supplier. SAMPLE 1 2 3 4 5 6 7 8 9 10 IRREGULARITIES 3 5 2 6 5 4 6 3 4 5 Determine the c¯�¯ , Sc�� , UCL and LCL for a c-chart with z = 2. Note: Round your answers to 2 decimal places.   Suppose the next five rolls from the supplier had three, two, five, three, and seven irregularities. Is the supplier process under control? multiple choice Yes No

A shirt manufacturer buys cloth by the roll from a supplier. For setting up a control chart to manage the irregularities (e.g., loose threads and tears), the following data were collected from a sample provided by the supplier.   Sample Irregularities 1 2 2 1 3 4 4 2 5 0 6 4 7 3 8 0 9 2 10 1 Total 19   Calculate the LCL and UCL for a c-chart with z=2 LCL= 0, UCL = 4.66 LCL= 0, UCL = 3.28 LCL= -0.86, UCL = 3.28 LCL= -0.86, UCL = 3.51 LCL= -0.86, UCL = 4.66