The Expected (Mean)life of a Particular Type of Light Bulb

question 10

Multiple Choice

The expected (mean) life of a particular type of light bulb is 1,000 hours with a standard deviation of 50 hours. The life of this bulb is normally distributed. What is the probability that a randomly selected bulb would last longer than 1150 hours?

• A) 0.4987
• B) 0.9987
• C) 0.0013
• D) 0.5013
• E) 0.5513

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Definitions:

Self-promotion

The act of highlighting one’s own skills, achievements, or qualities to advance personal or professional interests.

Influence

The ability to influence the personality, growth, or actions of an individual or entity.

Two-Stage Attribution Model

A psychological theory that describes how individuals infer the causes of their own or others' behavior in two steps: first identifying the behavior, then attributing it to internal or external causes.

Manager

An individual responsible for controlling or administering an organization or group of staff.