The Mean Life of a Particular Brand of Light Bulb

question 47

Multiple Choice

The mean life of a particular brand of light bulb is 1200 hours.If you know that at about 95% of this brand of bulbs will last between 1100 and 1300 hours, then what is the standard deviation of the light bulbs' life?

• A)25
• B)50
• C)75
• D)100
• E)200

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Definitions:

Prognosis

An informed prediction of the likely course and outcome of a disease or condition based on scientific knowledge and patient-specific factors.

Identification

The psychological process wherein an individual assimilates an aspect, property, or attribute of the other.

Diagnosis

The identification of the nature and cause of a certain phenomenon, often used in the context of medical conditions.

Etiology

Research focused on finding out what causes diseases or health conditions to occur.