SCENARIO 15-4
a Factory Supervisor Is Concerned That the Time

question 235

Multiple Choice

SCENARIO 15-4
A factory supervisor is concerned that the time it takes workers to complete an important production task (measured in seconds) is too erratic and adversely affects expected profits.The supervisor proceeds by randomly sampling 5 individuals per hour for a period of 10 hours.The sample mean and range for each hour are listed below.
$$\begin{array} { cc c } \underline { \text { Hour } } & \underline { X } & \underline { R } \\1 & 18.4 & 25 \\2 & 16.9 & 27 \\3& 23.0 & 30 \\4 & 21.2 & 23 \\5 & 21.0 & 24 \\6 & 24.0 & 25 \\7&19.3&12\\8 & 15.8 & 14 \\9 & 20.0 & 13 \\10 & 23.0 & 11\end{array}$$ She also decides that lower and upper specification limit for the critical-to-quality variable should be
10 and 30 seconds, respectively.
-Referring to SCENARIO 15-4, suppose the sample mean and range data were based on 6 observations per hour instead of 5.How would this change affect the lower and upper control limits of an R chart?

• A)LCL would increase; UCL would decrease.
• B)LCL would remain the same; UCL would decrease.
• C)Both LCL and UCL would remain the same.
• D)LCL would decrease; UCL would increase.

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Definitions:

Average Assets

The mean value of a company’s assets over a given time frame, often used in financial analysis to assess asset utilization efficiency.

Full Cost

The total cost of producing a product or service, including all direct, indirect, fixed, and variable costs.

Price-Fixing Contracts

Agreements between competitors to set prices at a certain level, which is illegal in many jurisdictions because it undermines free market competition.

Competition

The rivalry among businesses to attract customers and achieve market dominance.