Question: A quality analyst wants to construct a sample mean chart for controlling a packaging process. He knows from past experience that the process standard deviation
A quality analyst wants to construct a sample mean chart for controlling a packaging process. He knows from past experience that the process standard deviation is two ounces. 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 | 23 | 24 |
| Tuesday | 23 | 21 | 19 | 21 |
| Wednesday | 20 | 19 | 20 | 21 |
| Thursday | 18 | 19 | 20 | 19 |
| Friday | 18 | 20 | 22 | 20 |
(a) Calculate upper and lower control limits that allow for natural variations.
(b) Is this process in control?
Step by Step Solution
There are 3 Steps involved in it
Get step-by-step solutions from verified subject matter experts
