It's all one question!

Note: 1. A spreadsheet containing data for problem 1 and 2 is available on Blackboard. 2. All the data in this homework are fictitious. Problem 1 UTire is an automotive tire company. As a quality inspector for UTire, you monitor the average life cycle of passenger car tires coming off of a production line. The following sample data (in miles) was collected when the production process was known to be in control. Each of the 7 samples consisted of 5 observations: Life Cycle (mile) Sample Number 1 2 3 4 5 1 81081 80686 78401 79125 81158 2 80743 81554 80911 79887 80279 3 78372 80480 81647 78039 80673 4 80728 78117 79704 81586 78180 5 79230 81724 79186 78198 78880 6 78645 81531 78287 81273 81884 7 80398 79196 80845 80100 78809 a. Calculate the 30 upper and lower control limits and the center lines for both the mean (X) and range (R) charts. Use the "factors" from the class slides. b. UTire recently implemented a new rubber forming technology in order to reduce the production time. To evaluate the impact of the new technology on tire life cycle, the following 10 samples have been collected after the change. Life Cycle with New Technology (mile) 2 3 Sample Number 1 4 5 79053 1 81842 78009 81612 80349 2 82000 81283 80105 82270 83645 3 83527 81343 82484 77732 76180 4 79504 80655 78982 82394 83021 5 83174 82484 79225 82015 83164 6 82024 79766 81146 78253 81762 7 80624 82041 80113 80434 79041 8 77591 76560 76961 78417 80899 9 78566 81949 81650 81288 80536 10 79114 83903 82587 78166 77017 1 1. Plot the sample means and sample ranges for each of the 10 samples on the appropriate control chart using the upper and lower control limits and center lines you computed in part (a). 2. Based on your results from both charts, is the production process still in control? Why or why not