The Number of Phone Calls Arriving at a Switchboard Each

question 14

Multiple Choice

The number of phone calls arriving at a switchboard each hour has been recorded, and the following frequency distribution has been developed.
$$\begin{array} { l c } \text { Class Interval } & \text { Frequency } \\20 \text {-under } 40 & 30 \\40 \text {-under } 60 & 45 \\60 \text {-under } 80 & 80 \\80 \text {-under } 100 & 45\end{array}$$
What is the midpoint of the last class?

• A)80
• B)100
• C)95
• D)90
• E)85

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Definitions:

Premium Per Person

The amount of money charged per individual for insurance coverage.

Volume Discounts

Price reductions offered to buyers purchasing in large quantities, used as an incentive to increase sales volume.

Transportation Costs

Expenses associated with the movement of goods or individuals from one location to another, including factors like fuel, labor, and maintenance.

Returns to Scale

The rate at which output increases as inputs are increased proportionally in the production process.