Quiz 8

Question 1

Reasons for employing sampling techniques versus 100% inspection include all of the following, except:

Answer 1

100% inspection costs less than sampling.

Question 2

Which is true of process charts, in general?

Answer 2

The process for developing a process chart is the same for almost all charts.

Question 3

[Dispersion of a process is one of two important variables typically measured for a particular product in a process. Which is true of charting process dispersion?]

Answer 3

The R chart measures dispersion of a process and can be computed by measuring the difference between high and low values of a subgroup of items.

Question 4

Which of the following is correct regarding interpreting control charts? Assume a control chart employs three standard deviation limits and one point is outside the control limits.

Answer 4

The chance that the process is stable is less than 1%.

Question 5

Which is a correct match of terminology to description in a control chart?

Answer 5

Process drift – seven points that are all either increasing or decreasing indicate that machines may be drifting out of alignment.

Erratic behavior – large jumps of more than three or four standard deviations.

Process run – five points above or below center indicate the process has shifted.

Question 6

[The s chart (standard deviation chart) would be useful in measuring dispersion when producing]

Answer 6

a) parts that work together as part of a machine.

b) tools used to measure the performance of other tools.

Question 7

[One would expect]

Answer 7

much more variability in population distributions vs. sampling distributions.

Question 8

Your variables control chart displays two points in succession farther than two standard deviations from the mean. You should:

Answer 8

Investigate and take action(s) because this is unlikely to be random variation.

Question 9

[Which is true of an X chart?]

Answer 9

X chart limits are termed “natural limits.”