A Quality Analyst Wants to Construct a Control Chart for Determining

Multiple Choice

A Quality Analyst wants to construct a control chart for determining whether three machines,all producing the same product,are under control with regard to a particular quality variable.Accordingly,he sampled four units of output from each machine,with the following results: Using the factors for three sigma control limits,what are the sample range (R) chart upper and lower control limits?

A) 11.14 and 0
B) 9.88 and 0
C) 8.66 and 0
D) 4.94 and 0
E) 4.33 and 0