SCENARIO 15-3
a Quality Control Analyst for a Light Bulb

question 121

Multiple Choice

SCENARIO 15-3
A quality control analyst for a light bulb manufacturer is concerned that the time it takes to produce a batch of light bulbs is too erratic.Accordingly, the analyst randomly surveys 10 production periods each day for 14 days and records the sample mean and range for each day.
$\begin{array}{ccc}\underline{\text { Day }}&\underline{ \bar{X} \text { (inminutes) }}& \underline{\text { R}}\\1 & 58.5 & 5.1 \\2 & 47.6 & 7.8 \\3 & 64.3 & 6.1 \\4 & 60.6 & 5.7 \\5 & 63.7 & 6.2 \\6 & 57.5 & 6.0 \\7 & 55.0 & 5.4 \\8 & 54.9 & 6.1 \\9 & 55.0 & 5.9 \\10 & 62.7 & 5.0 \\11 & 61.9 & 7.1 \\12 & 60.0 & 6.5 \\13 & 58.3 & 5.9 \\14 & 52.0 & 5.2\end{array}$
-Referring to SCENARIO 15-3, suppose the analyst constructs an X chart to see if the production process is in-control.What is the lower control limit (LCL) for this chart?

• A)47.60
• B)56.15
• C)57.15
• D)58.05

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Definitions:

Automobile Factory

A manufacturing facility where cars are produced, involving assembly lines and parts fabrication processes.

Null Hypothesis

An assumption in statistical analysis that proposes no significant relationship or difference exists among specified groups or variables.

Energy Consumption

The amount of energy utilized by specific processes, devices, systems, or by a society, typically measured in units such as joules, kilowatt-hours, or calories.

U.S. Regions

Geographic areas in the United States characterized by specific climatic, cultural, economic, or demographic traits.