A Manufacturer of Windows Produces One Type That Has a Plastic

question 68

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,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 = = 50.05,and average range of 8.85.Assuming that the process is in statistical control,calculate the natural tolerance limits for the process.

• A)[45.75,54.35]
• B)[37.16,62.94]
• C)[42.40,57.70]
• D)[47.50,52.60]

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Definitions:

Perpendicularity

The state or condition of being perpendicular, meaning two lines or planes intersect at a right angle (90 degrees) to each other.

Tolerance of Form

Specifies the allowable deviation from the ideal shape of an object without specifying size, ensuring parts fit together correctly.

Tolerances of Size

Specifies the permissible limits of variation in an object's size, critical for ensuring parts fit together properly in manufacturing.

Cylindrical Tolerance Zone

A specified range of acceptable measurements or dimensions for the diameter or roundness of cylindrical parts, ensuring proper fit and function.