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.

1. The mean of all sample means is:

A) 20

B) 23

C) 19

D) 21

E) 20.6

2. Calculate 3 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 = 22.21; LCL = 18.98

(e) UCL = 23.7; LCL = 17.5

3. Is this process in control?

(a) Monday sample is above the UCL; all others are within limits. The process is out of control.

(b) Tuesday sample is above the UCL; all others are within limits. The process is out of control.

(c) Wednesday sample is below the LCL; all others are within limits. The process is out of control.

(d) Thursday sample is below the LCL; all others are within limits. The process is out of control.

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

Package 1 Weight Package 2 Package 3 Package 4 22 Day Monday Tuesday Wednesday Thursday Friday 19 21