Reference Factors for calculating three-sigma limits for the x-chart and R-chart Size of Sample Factor for UCL and LCL (n) for x-chart (A2) Factor for LCL for R-Chart (D3) Factor for UCL for R-Chart (D4) 2 0 3 0 4 0 5 0 1.880 1.023 0.729 0.577 0.483 0.419 0.373 0.337 0.308 6 7 0 3.267 2.575 2.282 2.115 2.004 1.924 1.864 1.816 1.777 8 0.076 0.136 0.184 0.223 9 10 The Money Pit Mortgage Company is interested in monitoring the performance of the mortgage process. Fifteen samples of five completed mortgage transactions each were taken during a period when the process was believed to be in control. The times to complete the transactions were measured. The means and ranges of the mortgage process transaction times, measured in days, are as follows: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Sample Mean Range 14 5 14 9 11 10 13 6 8 6 11 13 12 14 13 17 11 12 9 15 8 6 10 11 17 12 14 8 11 13 Subsequently, samples of size 5 were taken from the process every week for the next 10 weeks. The times were measured and the following results obtained: 16 17 18 19 20 21 22 23 24 25 Sample Mean Range 9 6 12 15 10 19 11 13 14 14 17 10 15 8 9 8 6 16 13 12 Click the icon to view the table of factors for calculating three-sigma limits for the x-chart and R-chart. a. Construct the control charts for the mean and the range, using the original 15 samples. Set up the R-chart by specifying the center line and three-sigma control limits below. (Enter your responses rounded to two decimal places.) R-chart = UCLR R LCLR = = Click the icon to view the table of factors for calculating three-sigma limits for the X-chart and R-chart. a. Construct the control charts for the mean and the range, using the original 15 samples. Set up the R-chart by specifying the center line and three-sigma control limits below. (Enter your responses rounded to two decimal places.) R-chart UCLR-23.27 R = - 11.00 LCLR- 0 Set up the x-chart by specifying the center line and three-sigma control limits below. (Enter your responses rounded to two decimal places.) x-chart UCL-22.35 - 16.00 LCL = 9,63 b. On the control charts developed in part (a), plot the values from samples 16 through 25 and comment on whether the process is in control. Set up the x-chart by specifying the center line and three-sigma control limits below. (Enter your responses rounded to two decimal places.) x-chart UCL; - 22.35 x 16.00 | : LCL- 8 9.65 b. On the control charts developed in part (a), plot the values from samples 16 through 25 and comment on whether the process is in control. Choose the correct R-chart for the data below. , OC OB D 28 UCLR 28, UCLR 16 UCLR 16 UCLR 12- LCLR w 4- LCLR - o1 15 17 19 21 23 25 Sample Number LCN oh 15 17 19 2125 Sample Number 15 17 19 21 23 25 Sample Number LCL or 15 17 19 21 23 25 Sample Number Choose the correct X-chart for the data below. OA . OC OD 26- 22 UCL UCL 18 14 26 UCL; 22 18 14 10 LCLC 15 17 19 21 23 25 Sample Number 26 22 UCL- 18 14 10 LC 15 17 19 21 23 25 Sample Number sem 26- 22 18 14 10 6 LCL 15 17 19 21 23 25 Sample Number 10- VDA LCL 15 17 19 21 23 25 Sample Number