Determine the correct sample size for each of the following problems. You must show the equation you used, the values you substituted into that equation, and your final value of "n" to three decimal places before you round the value of "n" to a whole number. In other words, follow the examples shown on the lecture page for this assignment.
1. After a brief time study on a delivery job, the data showed an average time to do the delivery job of 5.7 minutes with a standard deviation of 0.35 minutes. If we use an alpha value of 2%, and we want our final estimate to be within 0.1 minutes of the true value, how large a sample should be taken?
2. A time study analyst has collected some preliminary data on a manufacturing job. The average time to do the job is 13.4 minutes with a standard deviation of 0.9 minutes. The analyst wants the final estimate to be within 0.5 minutes of the true time, and the alpha value has been established at 7%. How large a sample should be studied?
3. The office operations of the company currently permits a personal factor of 22%. If the alpha value is equal to 6% and the acceptable error is 8%, how large a sample must be taken?
4. The manufacturing area has had a historical delay percentage of 10.5%. Management wants to verify that percentage using an alpha value of 9% and they are willing to tolerate an acceptable error of 4%. How large a sample will be necessary?