Using samples of 190 credit card statements, an auditor found the following: Use Table-A.

Sample	1	2	3	4
Number with errors	5	3	5	12

a. Determine the fraction defective in each sample. (Round your answers to 4 decimal places.)

Sample	Fraction defective
1	.0263 .0263 Correct
2	.0158 .0158 Correct
3	.0263 .0263 Correct
4	.0632 .0632 Correct

b.If the true fraction defective for this process is unknown, what is your estimate of it? (Round your answer to 1 decimal place. Omit the "%" sign in your response.)

Estimate 3.3 3.3 Correct %

c. What is your estimate of the mean and standard deviation of the sampling distribution of fractions defective for samples of this size? (Round your intermediate calculations and final answers to 4 decimal places.)

Mean	.0329 .0329 Correct
Standard deviation	.0180 .0180 Incorrect

d.What control limits would give an alpha risk of .03 for this process? (Round your intermediate calculations to 4 decimal places. Round your "z" value to 2 decimal places and other answers to 4 decimal places.)

z = 2.17, ____ to ____

e.What alpha risk would control limits of .0470 and .0188 provide? (Round your intermediate calculations to 4 decimal places. Round your "z" value to 2 decimal places and "alpha risk" value to 4 decimal places.)

z = alpha risk =