Concept explainers
Case Summary: In Gr’s Garage, the proportion of average number of customers who comes back again for the same fault is 0.10, during the warranty period of 30 days. Every month, 100 customers are tracked by Gr, in order to find out whether they are returning for same repair works during the warranty period and the same is plotted as proportion to report progress against goal. By setting the control limits on both sides of goal, at two standard deviations, the control limit for the chart needs to be determined. From the sample group 8 customers out of 100, has returned for repairs, for which the repair process is under control or not, needs to be assessed.
Interpretation: The standard deviation gives information as to how various values are spread out when compared to the mean value.
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Operations Management: Processes and Supply Chains (12th Edition) (What's New in Operations Management)
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