As the production manager for an electronic circuit company you have
encountered the following situation.

Part 1
A process for producing electronic circuits has achieved very high
yield levels. An average of only 10 defective parts per million is
currently produced.

1.What are the upper and lower control limits for a sample size of 100? 
2.Recompute the upper and lower control limits for a sample size of 10,000? 
3.Which of these two sample sizes would you recommend? Explain. 

Part 2
Management has reconsidered the method of quality control and has
decided to use process control by variables instead of attributes. For
variables control a circuit voltage will be measured based on a sample
of only five circuits. The past average voltage for samples of size 5
has been 3.1 volts, and the range has been 1.2 volts.
1.What would the upper and lower control limits be for the resulting
control charts (average and range)?
2.Five samples of voltage are taken with the results in the table
below. What action should be taken if any?
3.Discuss the pros and cons of using this variables control chart
versus the control chart discussed in the first part of the
assignment. Which do you prefer?

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Clarification of Question by verifier-ga on 06 Nov 2004 08:37 PST

Use the following link below as a point-of-reference.

http://highered.mcgraw-hill.com/sites/dl/free/0072498919/95884/sch98919_ch09.pdf