You want to determine the control lines for a p-chart for quality control purposes.If the desired confidence level is 99 percent, which of the following values for "z" would you use in computing the UCL and LCL?
A)0.99
B)2
C)2.58
D)3
E)None of these

Question

Quizplus · Accepted Answer

To calculate the control limits for a p-chart at a 99% confidence level, we use a z-value that corresponds to the area between the mean and the control limits of 0.005 in each tail of the distribution. This corresponds to a z-value of 2.58. Therefore, the UCL and LCL would be calculated using a z-value of 2.58.

You Want to Determine the Control Lines for a P-Chart