A Manufacturer of Windows Produces One Type That Has a Plastic

question 47

Multiple Choice

A manufacturer of windows produces one type that has a plastic coating.The specification limits for the plastic coating are 30 and 70.From time to time the plastic coating can become uneven.Therefore,in order to keep the coating as even as possible,thickness measurements are periodically taken at four different locations on the window.15 subgroups were observed,each consisting of four thickness measurements,with the following results: mean of the means = $\overline { \overline{ x } }$

= 50.05,and average range = 8.85.Calculate the center line for the X-bar chart.

• A)50.05
• B)8.85
• C)4.12
• D)3.34

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Definitions:

Interindustry Competition

Competition among firms that operate in different industries but compete for the same set of customers or inputs.

Oligopolistic Producers

Firms within a market structure where a small number of companies have the majority of market share and thus can significantly influence price and production levels.

Purely Competitive

Describes a market structure where many sellers offer identical products, and no single seller can influence the market price.

Concentration Ratio

A measure used in economics to assess the degree of market concentration by summing the market shares of the top firms in the industry.