A Catalog Company That Receives the Majority of Its Orders

question 86

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 waiting time was found to be a random variable best approximated by an exponential distribution with a mean length of waiting time equal to 3 minutes (i.e. the mean number of calls answered in a minute is 1/3) . 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:

N2 Sleep

A stage of sleep within the non-REM cycle characterized by sleep spindles and K-complexes, marking a deeper sleep than N1 and preceding the deepest, N3 stage.

N3 Sleep

Third stage of non-REM sleep, characterized by deep sleep and the presence of delta waves in the brain, essential for restorative sleep.

Coping Hypothesis

A theory suggesting how individuals adapt to stressful situations, balancing and managing stress to maintain psychological well-being.

Sigmund Freud

A founding figure of psychoanalysis, Freud developed theories about the unconscious mind, the structure of personality, and the stages of psychosexual development.