A process that produces titanium forgings for automobile turbocharger wheels is to be controlled through use of a fraction nonconforming chart. Initially, one sample of size 150 is taken each day for 20 days, and the results shown here are observed.
(a) Establish a control chart to monitor future production.
(b) What is the smallest sample size that could be used for this process and still give a positive lower control limit on the chart?
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