A Quality Analyst Wants to Construct a Sample Mean Chart

question 50

Multiple Choice

A quality analyst wants to construct a sample mean chart for controlling a packaging process. He knows from past experience that whenever this process is under control, package weight is normally distributed with a mean of 20 ounces and a standard deviation of two ounces. Each day last week, he randomly selected four packages and weighed each: $$\begin{array} { r } { \text { Weight (ounces) } }\\\begin{array} { l l l l l } \text { Day } \\\hline \text { Monday } & 23 & 22 & 23 & 24 \\\text { Tuesday } & 23 & 21 & 19 & 21 \\\text { Wednesday } & 20 & 19 & 20 & 21 \\\text { Thursday } & 18 & 19 & 20 & 19 \\\text { Friday } & 18 & 20 & 22 & 20\end{array}\end{array}$$ If he uses upper and lower control limits of 22 and 18 ounces, what is his risk (alpha) of concluding this process is out of control when it is actually in control (Type I error) ?

• A) 0.0026
• B) 0.0456
• C) 0.3174
• D) 0.6826
• E) 0.9544

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Definitions:

Domestic Price

The price level of goods and services within a country's border, reflecting the domestic market's supply and demand conditions.

Shoes

Footwear crafted from various materials designed to protect and comfort the human foot while enabling mobility, often reflecting fashion and social status.

International Trade

The exchange of goods and services across national borders, driven by the principle of comparative advantage.

Economic

Pertaining to the production, distribution, and use of income, wealth, and commodities.