A Catalog Company That Receives the Majority of Its Orders

question 104

Multiple Choice

A catalog company that receives the majority of its orders by telephone conducted a study to determine how long customers were willing to wait on hold before ordering a product. The length of time was found to be a random variable best approximated by an exponential distribution with a mean equal to 3 minutes. What proportion of customers having to hold more than 4.5 minutes will hang up before placing an order?

• A) 0.22313
• B) 0.48658
• C) 0.51342
• D) 0.77687

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Definitions:

Raw Scores

The initial, unadjusted scores obtained directly from the number of questions answered correctly on an assessment or test.

Test-retest Reliability

The consistency of a test's results when the same individuals take the same test again after a period of time, measuring its stability over time.

Z score

A numerical metric that represents how a specific value's deviation relates to the average of a dataset, quantified by the number of standard deviations away from that average.

Normal Curve

A bell-shaped curve, also known as a Gaussian distribution, representing the spread of a variable in a way that most values cluster around the mean.