Instruction 18-10
a Factory Supervisor Is Concerned That the Time

question 68

Multiple Choice

Instruction 18-10
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 five 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.
$\begin{array}{ll}\begin{array}{c}\text { Hour }\\\hline1\\2 \\3 \\4 \\5 \\6 \\7 \\8 \\9 \\10\end{array}\begin{array}{r}\overline{X}&R\\\hline{18.4} & 25 \\16.9 & 27 \\23.0 & 30 \\21.2 & 23 \\21.0 & 24 \\24.0 & 25 \\19.3 & 12 \\15.8 & 14 \\20.0 & 13 \\23.0 & 11\end{array}\end{array}$
-Referring to Instruction 18-10,suppose the supervisor constructs an R chart to see if the variability in collection times is in control.What are the lower and upper control limits for this R chart?

• A)-2.28,42.28
• B)0,43.13
• C)-2.33,43.13
• D)0,42.28

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Definitions:

Problem

A situation, question, or issue that presents difficulty or uncertainty and necessitates a solution or answer.

Insight

A deep understanding of a person or situation, often resulting in a clear and sometimes sudden discernment of a solution to a problem.

Fixation

An obsessive focus or attachment to certain behaviors, people, or developmental stages, often hindering emotional development.

Mental Set

A cognitive tendency to approach situations in a fixed way based on previous experiences, potentially inhibiting problem-solving.