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Problem 10-25 Resistors for electronic circuits are manufactured on a high-speed automated machine. The machine is set up to produce a large run of resistors of 1,000 ohms each. Use Exhibit 10.13. To set up the machine and to create a control chart to be used throughout the run, 15 samples were taken with four resistors in each sample. The complete list of samples and their measured values are as follows: Use three-sigma control limits. 995 SAMPLE NUMBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 READINGS (IN OHMS) 1010 991 985 986 996 1009 994 990 1003 1015 1008 1015 1020 1009 998 1013 1019 1006 993 994 1001 994 1005 989 992 982 1020 1001 986 996 1006 989 1005 1007 992 1007 1006 979 996 1006 997 989 1019 996 991 1011 991 991 989 1003 993 988 984 1013 1002 1005 992 a. Calculate the mean and range for the above samples. (Round "Mean" to 2 decimal places and "Range to the nearest whole number.) Mean Sample Number 1 2 3 4 5 6 7 Range 24 15 31 35 29 19 24 56 59 54 54 51 33 52 43 992.250 998.75 994.251 999.25 9890 989.75 987.50 1002.750 991 1005 1010.75 1005.750 100251 10020 991.250 8 9 10 11 12 13 14 15 b. Determine X and R. (Round your answers to 3 decimal places.) 997.45 38.61 c. Determine the UCL and LCL for a Xchart. (Round your answers to 3 decimal places.) UCL LCL 1025.63 969.27 d. Determine the UCL and LCL for R-chart. (Leave no cells blank - be certain to enter "0" wherever required. Round your answers to 3 decimal places.) UCL LCL e. What comments can you make about the process? The process is in statistical control. The process is out of statistical control