The Random Variable X Is the Number of Occurrences of an Event

question 15

Multiple Choice

The random variable x is the number of occurrences of an event over an interval of ten minutes. It can be assumed that the probability of an occurrence is the same in any two time periods of an equal length. It is known that the mean number of occurrences in ten minutes is 5.3. The expected value of the random variable x is

• A) 2.
• B) 5.3.
• C) 10.
• D) 2.30.

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Definitions:

Mutually Exclusive

Situations or events that cannot occur at the same time—choosing one precludes the selection of the other.

Negative Net Present Value

A financial metric indicating that the present value of cash inflows is less than the present value of cash outflows, suggesting the investment is not financially viable.

Initial Cost

The upfront expense incurred to purchase an asset or to initiate a project.

Net Present Value

A calculation that compares the value of a dollar today to the value of that same dollar in the future, taking inflation and returns into account.