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

question 66

Multiple Choice

If x, the time (in minutes) to complete an oil change job at 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:

Correlation Coefficient

A statistical measure that calculates the strength and direction of the linear relationship between two variables.

Correlation Coefficient

An index assessing the power of association between a pair of variables.

Dependent Variable

A dependent variable is the outcome or response that researchers are interested in explaining or predicting, changing in response to manipulation of the independent variable.

Independent Variable

The variable in an experimental or observational study that is manipulated or categorized to observe its effect on the dependent variable.