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

question 168

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 are the lower and upper control limits of this chart?

• A)10.00, 30.00
• B)8.49, 32.03
• C)5.39, 35.13
• D)4.96, 35.56

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Definitions:

Molecular Evidence

Refers to data derived from DNA, RNA, and protein sequences that is used to support hypotheses about the evolutionary relationships between organisms.

Biomarkers

Biological molecules found in blood, other body fluids, or tissues that are a sign of a normal or abnormal process, or of a condition or disease.

Fossil Record

The collection of preserved remains or traces of animals, plants, and other organisms from the past.

Grasses

A family of plants (Poaceae) that includes cereals, bamboos, and the grasses of natural grassland and cultivated lawns and pastures.