If X, the Time (In Minutes)to Complete an Oil Change $\le$

question 89

Multiple Choice

If x, the time (in minutes) to complete an oil change job at a certain auto service station, is uniformly distributed over the interval 20 to 30, inclusively (20 $\le$ x $\le$ 30) , then the standard deviation of this distribution is ___.

• A)unknown
• B)8.33
• C)0.833
• D)2.89
• E)1.89

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Definitions:

Price Hike

An increase in the price of goods or services, which can be due to various factors including increased production costs or higher demand.

Net Operating Income

A measure of a company’s profitability, calculated as revenues less operating expenses excluding taxes and interest.

Traceable Fixed Expense

A fixed cost that can be directly linked to a specific segment of the business and would be eliminated if the segment ceased operations.

Percentage Change

A calculation that shows how much a quantity has increased or decreased in percentage terms over a period.