# solution

A quality analyst wants to construct a sample mean chart for controlling a packaging process. Each day last week, he randomly selected four packages and weighed each. The data from that activity appears below.

Weight

Day Package 1 Package 2 Package 3 Package 4

Monday 23 22 24 24

Tuesday 23 21 19 22

Wednesday 21 19 21 21

Thursday 18 19 20 20

Friday 18 21 22 22

15. Calculate 3s upper and lower control limits for the Mean.

(a) UCL = 23.05; LCL = 18.15

(b) UCL = 22.64; LCL = 18.56

(c) UCL = 26.6; LCL = 14.6

(d) UCL = 23.04; LCL = 18.96

(e) UCL = 23.7; LCL = 17.5

16. Is this process in control?

(a) Monday sample is above the UCL; all others are within limits. The process is not in control.

(b) Tuesday sample is above the UCL; all others are within limits. The process is not in control.

(c) Wednesday sample is below the LCL; all others are within limits. The process is not in control.

(d) Thursday sample is below the LCL; all others are within limits. The process is not in control.

(e) All samples are within limits. The process is in control.

25. The main difference between Cp and Cpk is that

A) Cp values above 1 indicate a capable process, Cpk values above 2 indicate a capable process

B) Cp values for a given process will always be greater than or equal to Cpk values

C) both are identical

D) All of the above

E) None of the above