A Design Engineer Wants to Construct a Sample Mean Chart

question 70

Multiple Choice

A design engineer wants to construct a sample mean chart for controlling the service life of a halogen headlamp his company produces. He knows from numerous previous samples that this service life is normally distributed with a mean of 500 hours and a standard deviation of 20 hours. On three recent production batches, he tested service life on random samples of four headlamps, with these results: $$\begin{array} { r } { \text { Service Life (hours) } }\\\begin{array} { l l l l l } \text { Sample } & \\\hline 1 & 495 & 500 & 505 & 500 \\2 & 525 & 515 & 505 & 515 \\3 & 470 & 480 & 460 & 470\end{array}\end{array}$$ What is the sample mean service life for sample 2?

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Definitions:

Cost Of Production Report

A document that details the total cost and production information for a specific period, used primarily in process costing settings.

Equivalent Units

A concept in costing used to convert partially completed goods into the equivalent of a number of fully completed units.

Process Cost Accounting

Process cost accounting is a method used to allocate production costs to units of output in continuous or repetitive manufacturing processes.

Materials Account

The materials account is used in accounting to track the cost of raw materials that are either in stock or used during the manufacturing process.