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

question 64

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.Which expression best describes this chart?

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

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Definitions:

Neanderthals

An extinct species or subspecies of archaic humans who lived in Eurasia until about 40,000 years ago.

Sound Travels

Sound travels through various mediums (such as air, water, and solids) as a wave of pressure variations, allowing us to hear by reaching and being interpreted by our ears.

Feet/Second

A unit of speed expressing the distance in feet traveled or covered in one second.