A Catalogue Company That Receives the Majority of Its Orders

question 73

Multiple Choice

A catalogue 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 2.8 minutes.
-What is the probability that a randomly selected caller is placed on hold fewer than 7 minutes?

• A) 0.9990881
• B) 0.917915
• C) 0.0009119
• D) 0.082085

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Definitions:

Double Bond

A chemical bond in which two pairs of electrons are shared between two atoms.

Lewis Structure

A representation of molecules where symbols for elements are used to represent nuclei and inner-shell electrons, and dots or dashes between symbols represent electron pairs forming covalent bonds.

Ammonia

A colorless gas with a distinct sharp smell, composed of nitrogen and hydrogen (NH3), used as a fertilizer, in cleaning products, and in the synthesis of various chemicals.

Lewis Structure

A representation of molecules showing all the atoms, valence electrons, and bonding between atoms as well as any lone pairs of electrons.