TABLE 17-4
a Factory Supervisor Is Concerned That the Time

question 64

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.
$\begin{array}{ccc} \underline { \text {Hour } }& \underline { \bar { X } } & \underline { R }\\1 & 18.4 & 25 \\2 & 16.9 & 27 \\3 & 23.0 & 30 \\4 & 21.2 & 23 \\5 & 21.0 & 24 \\6 & 24.0 & 25 \\7 & 19.3 & 12 \\8 & 15.8 & 14 \\9 & 20.0 & 13 \\10 & 23.0 & 11\end{array}$

She also decides that lower and upper specification limit for the critical-to-quality variable should be 10 and 30 seconds, respectively.
-Referring to Table 17-4, suppose the supervisor constructs an $\bar { X }$ chart to see if the process is in-control. Which expression best describes this chart?

• A) Decreasing trend
• B) In-control
• C) Increasing trend
• D) Individual outliers

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Definitions:

Piaget's Theory

A theory of cognitive development that outlines how children's abilities to think and reason progress through four distinct stages as they grow.

Conservation Task

A concept in developmental psychology that assesses a child’s ability to recognize that quantities remain the same despite changes in their shape or arrangement.

Beakers

Laboratory glassware with a wide body and a spout for pouring, commonly used in chemical experiments and procedures.

Class Inclusion Tasks

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