A company’s QC dept. has recorded the proportion of defective items for each of 500 monthly shipments of one of the computer components that the company produces (datain attached file).The QC dept. manager does not have time to review all of this data. Instead she would like to examine the proportions of defective items for a sample of these shipments.

a) Use Excel to generate a simple random sampleof size 25 from the given frame.

b) Compute the point estimate of the population meanfrom the sample selected in part a. What is the samplingerror in this case? Assume that the population consists of the proportion of defective items for each of the given 500 monthly shipments.

c) Determine a good approximation to the standard errorof the mean in this case.

d) Repeat parts b and c after generating a simple random sample of size 50 from the given frame.

See the attached file.

Part a)

Sample 1

Random No Set …

The solution uses Excel to generate simple random samples. The point estimate of the population mean from the sample selected is determined.