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

question 172

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 supervisor constructs an X chart to see if the process is in-control.What is the center line of the chart?

• A)20.00
• B)20.26
• C)21.00
• D)24.26

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Definitions:

Distinctions

Differences or unique characteristics that set someone or something apart from others.

Influence Attempts

Efforts made by individuals or groups to change the thoughts, feelings, or behaviors of others through various means, including persuasion and coercion.

Detrimental

Inflicting injury or destruction.

Followers

Individuals who support, admire, or look up to a leader or person of influence, often helping to carry out their vision or ideas.