Question: What is the statistical process chart used to control the number of defects per unit of output?

c-chart

p-chart

x-bar chart

AOQ chart

R-chart

Answer: c-chart

Question:

Answer: display upper and lower limits for process variables or attributes and signal when a process is no longer in control.

Question:

Answer: likely out of control and the cause should be investigated.

Question: The number of late insurance claim payouts per 100 should be measured with what type of control chart?

x-bar chart

R-chart

p-chart

either p-chart or c-chart

c-chart

Answer: p-chart

Question: The causes of variation in statistical process control are:

natural causes and assignable causes.

cycles, trends, seasonality, and random variations.

producer’s causes and consumer’s causes.

Type I and Type II.

mean and range.

Answer: natural causes and assignable causes.

Question: A nationwide parcel delivery service keeps track of the number of late deliveries (more than 30 minutes past the time promised to clients) per day. They plan on using a control chart to plot their results. Which type of control chart(s) would you recommend?

x-bar chart

c-chart

both x-bar chart and R-chart

both p-chart and c-chart

p-chart

Answer: c-chart

Question: The normal application of a p-chart is in:

process capability ratio computations.

acceptance sampling by variables.

process sampling by variables.

acceptance sampling by attributes.

process sampling by attributes.

Answer: process sampling by attributes.

Question: Assignable causes:

are within the limits of a control chart.

are also referred to as “chance” causes.

depend on the inspector assigned to the job.

are not as important as natural causes.

are causes of variation that can be identified and investigated.

Answer: are causes of variation that can be identified and investigated.

Question:

Answer: c-chart

Question: Natural variations:

lead to occasional false findings that processes are out of control.

are the same as assignable variations.

are variations that are to be identified and investigated.

play no role in statistical process control.

are variations that can be traced to a specific cause.

Answer: lead to occasional false findings that processes are out of control.