The Number of Phone Calls Arriving at a Switchboard Each

question 55

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 relative frequency of the second class?

• A)0.455
• B)0.900
• C)0.225
• D)0.750
• E)0.725

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Definitions:

Circular-Flow Model

A model that illustrates the movement of resources and money between firms and households in an economy.

Capital

Wealth in the form of money or other assets owned or employed in business by an individual, firm, or country.

Wages and Income

Represents the earnings received by laborers for their work and can include salaries, wages, and other forms of compensation.

Circular-Flow Diagram

A visual model that shows how goods, services, and money move through the economy in a continuous, circular flow between households and firms.