TABLE 17-4 A Factory Supervisor Is Concerned That the Time It Takes

question 99

Multiple Choice

TABLE 17-4
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.

She also decides that lower and upper specification limit for the critical-to-quality variable should be 10 and 30 seconds, respectively.
-Referring to Table 17-4, 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:

Physical Coordination Skills

Abilities that involve the use of the body's muscles in a synchronized manner to perform tasks efficiently and effectively.

Experimental

Experimental refers to a method or approach characterized by conducting controlled tests or trials to explore hypotheses and observe outcomes.

Random Assignment

A method used in experiments to equally distribute participants across various group treatments, ensuring that each group is statistically similar at the start.

Manipulating Factors

Variables that researchers deliberately change or manipulate in an experiment to see if they have an effect on some other variable.