TABLE 18-4
a Factory Supervisor Is Concerned That the Time

question 9

Multiple Choice

TABLE 18-4
A factory supervisor is concerned that the time it takes workers to complete an important production task (measured in seconds) is too erratic and adversely affects expected profits. The supervisor proceeds by randomly sampling 5 individuals per hour for a period of 10 hours. The sample mean and range for each hour are listed below.
$$\begin{array} { l l l l } \text { Hour } & \bar { X } & \text { R } \\\hline 1 & 18.4 & 25 \\2 & 16.9 & 27 & \\3 & 23.0 & 30 & \\4 & 21.2 & 23 & \\5 & 21.0 & 24 & \\6 & 24.0 & 25 & \\7 & 19.3 & 12 \\8 & 15.8 & 14 & \\9 & 20.0 & 13 & \\10 & 23.0 & 11 &\end{array}$$ She also decides that lower and upper specification limit for the critical-to-quality variable should be 10 and 30 seconds, respectively.
-Referring to Table 18-4, suppose the supervisor constructs an $\bar{ X}$ chart to see if the process is in-control. Which expression best describes this chart?

• A) cycles
• B) decreasing trend
• C) hugging the center line
• D) increasing trend

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Definitions:

Fixed Manufacturing Overhead

Ongoing expenses that do not change in total with the level of production or sales volume, such as salaries, rent, and insurance, associated specifically with the manufacturing process.

Variable Costing

An accounting method that includes only variable costs—those that change with production levels—in the cost of goods sold and inventory valuation.

Unit Product Cost

The total cost associated with producing one unit of a product, including direct materials, direct labor, and allocated overhead.

Segmented Income Statement

An income statement that separates costs and revenues into different segments, departments, or divisions of a business.