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 appear 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. What is the mean of all the sample means? [ Select ] ["20", "20.6", "23", "19"]
b. Calculate upper and lower 3-sigma x-bar chart control limits that allow for natural variations. [ Select ] ["15.5, 2.4", "23.6, 17.6", "20.6, 2.8", "6.3, 0"]
c. Based on the x-bar chart, is this process in control? [ Select ] ["cannot be determined", "no", "maybe", "yes"]
Step by Step Solution
There are 3 Steps involved in it
Get step-by-step solutions from verified subject matter experts
