Solve the Problem $$\text { quadratic mean } = \sqrt { \frac { \sum x ^ { 2 } } { n } }$$

question 58

Multiple Choice

Solve the problem.
-The quadratic mean (or root mean square) is usually used in physical applications. In power distribution systems, for example, voltages and currents are usually referred to in terms of their root mean square value.
The quadratic mean of a set of values is obtained by squaring each value, adding the results, dividing by the
Number of values (n) , and then taking the square root of that result, expressed as $$\text { quadratic mean } = \sqrt { \frac { \sum x ^ { 2 } } { n } }$$ Find the root mean square of these power supplies (in volts) : 110, 105, 10, 72.

• A) 148.5 volts
• B) 74.3 volts
• C) 42.1 volts
• D) 84.3 volts

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Definitions:

Variable Input

An input whose quantity can be changed in the short run to increase or decrease production.

Average Product of Labor

The output produced per unit of labor input, calculated by dividing total output by the total number of labor units used.

Variable Input

A production factor that can be adjusted in the short term to change the level of output, such as labor or raw materials.

Fixed Costs

Costs that do not change with the level of output produced by a firm, such as rent, salaries, and equipment costs.