Light Bulbs Are Normally Distributed with an Average Lifetime of 1000

question 108

Multiple Choice

Light bulbs are normally distributed with an average lifetime of 1000 hours and a standard deviation of 250 hours. The probability that a light bulb picked at random will last less than 1500 hours is about:

• A)97.72 percent.
• B)95.44 percent.
• C)75.00 percent.
• D)68.00 percent.

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Definitions:

Conscious Awareness

The state of being cognizant of and capable of recognizing one's own existence, sensations, thoughts, surroundings, etc.

Sensory Adaptation

The process by which sensory receptors become less sensitive to constant stimuli over time.

Cocktail-Party Effect

The ability to focus one's auditory attention on a particular stimulus while filtering out a range of other stimuli.

Sound Shadow

An area where sound waves are obstructed or diminished, often created by obstacles that prevent sound from reaching a listener directly.