X and R charts arc used to control a process by drawing subg

X and R charts arc used to control a process by drawing subgroups of five units every 2 h. Specifications on one critical characteristic are 2,119 plusminus 10. Product over specs may be reworked; if it must be scrapped. After 50 subgroups, summation X = 106,200.0 and summation R = 581.5. Determine 3-sign la control limits for X and R charts. Assuming that the process is in control and normally distributes, estimate sigma and determine the percent of product that must be reworked and that must scrapped.

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