David Desreumaux,VP of Human Resources of American First Banks (AFB),is $\alpha$

question 59

Multiple Choice

David Desreumaux,VP of Human Resources of American First Banks (AFB) ,is reviewing the employee training programs of AFB banks.Based on a recent census of personnel,David knows that the variance of teller training time in the Southeast region is 8,and he wonders if the variance in the Southwest region is the same number.His staff randomly selected personnel files for 15 tellers in the Southwest Region,and determined that their mean training time was 25 hours and that the standard deviation was 4 hours.Assume that teller training time is normally distributed.Using $\alpha$ = 0.10,the null hypothesis is ________.

• A)\(\mu\) = 25
• B) \(\sigma\)2 = 8
• C) \(\sigma\)2 = 4
• D) \(\sigma\)2 \(\le\) 8
• E)s² = 16

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Definitions:

Z-score

A statistic that measures the distance of a single data point from the mean, expressed in units of standard deviation.

Percentile

A statistical measure indicating the value below which a given percentage of observations in a group falls.

Standard Normal Curve

A symmetrical bell-shaped curve representing the distribution of a variable that has been standardized; it has a mean of 0 and a standard deviation of 1.

Area

A measure of the extent of a two-dimensional figure or shape in a plane, often measured in square units.