SCENARIO 19-3
A quality control analyst for a light bulb manufacturer is concerned that the time it takes to produce a batch of light bulbs is too erratic.Accordingly,the analyst randomly surveys 10 production periods each day for 14 days and records the sample mean and range for each day.

-Referring to Scenario 19-3,suppose the analyst constructs an R chart to see if the variability in production times is in-control.The R chart is characterized by which of the following?
A)Increasing trend
B)Decreasing trend
C)In-control
D)Points outside the control limits

Question

SCENARIO 19-3
A quality control analyst for a light bulb manufacturer is concerned that the time it takes to produce a batch of light bulbs is too erratic.Accordingly,the analyst randomly surveys 10 production periods each day for 14 days and records the sample mean and range for each day.

-Referring to Scenario 19-3,suppose the analyst constructs an R chart to see if the variability in production times is in-control.The R chart is characterized by which of the following?
A)Increasing trend 
B)Decreasing trend 
C)In-control 
D)Points outside the control limits

Quizplus · Accepted Answer

The R chart is used to monitor the variability of a process, and it is in-control if the range of the sample is within the control limits. No trend or points outside the control limits indicate that the process is stable and in-control.

SCENARIO 19-3 A Quality Control Analyst for a Light Bulb Manufacturer Is