Using samples of 190 credit card statements, an auditor found the following: sample 1 2 3 4

Number w/ errors 5 3 5 12

a. Determine the Fraction defective in each sample

b. If the true fraction defective for this process is unknow what is your estimate of it?

c. what is your estimate of the mean and standard deviation of the sampling distribution of fractions defective for samples of this size? (round to 4 decimal places)

d. What control limits would give an alpha risk of .03 for this process?

E. What alpha risk would control limits of .0470 and .0188 provide?

f. Using control limits of .0470 and .0188, is the process in control?

g. Suppose the long-term fraction defective of the process is known to be 2%. What are the values of the mean and standard deviation of the sampling distribution?