19 & 20

QUESTION 191.      

 

The UCL and LCL for an X_bar chart are 25 and 15 respectively. The central line is 20, and the process variability is considered to be in statistical control. The results of the next six sample means are 18, 23, 17, 21, 26, and 16. What should you do?

Answer

  

  

  

  

  

Nothing; the process is in control.
Explore the assignable causes because the second, fourth, and fifth samples are above the mean.
Explore the assignable causes because there is a run.
Explore the assignable causes because there is a trend
	Explore the assignable causes because the process is out of control

5 points   

QUESTION 201.        

The central line on a p-chart is 0.50 with a UCL of 0.65 and an LCL of 0.35. The results of the next six samples are 0.60, 0.37, 0.55, 0.48, 0.55, and 0.42. What should you do?

Answer

  

  

  

  

  Explore the assignable causes because the process is out of control

Nothing; the process is behaving as expected.

Explore the assignable causes because three observations are above the central line.

Explore assignable causes because there is a run.

Increase the sample size to get a better measure.