A New Extended-Life Light Bulb Has an Average Service Life

question 89

Multiple Choice

A new extended-life light bulb has an average service life of 750 hours, with a standard deviation of
50 hours. If the service life of these light bulbs approximates a normal distribution, about what
Percent of the distribution will be between 600 hours and 900 hours?

• A) 95%
• B) 68%
• C) 34%
• D) 99.7%

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Definitions:

Independent

Independent describes someone or something not influenced or controlled by others in matters of opinion, conduct, or other actions.

Convenience Sample

A non-random selection of participants from a population based on ease of access and availability, often used in exploratory research where representativeness is not a primary concern.

Probability Sample

A sampling method in which each member of the population has a known, non-zero chance of being selected, allowing for statistical inference to the larger population.

Sampling Frame

The list or database from which a statistical sample is drawn for a research study, encompassing all the members of the population being studied.