The Batteries Used by a Calculator Have Useful Lives That

question 30

Multiple Choice

The batteries used by a calculator have useful lives that follow a Normal distribution, with an average life of 2000 hours and a standard deviation of 200 hours. In the production process, the manufacturer draws random samples of 100 batteries and determines the mean useful life of the sample. What is the standard deviation _x of this mean?

• A) 25 hours
• B) 100 hours
• C) 2 hours
• D) 20 hours

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Definitions:

Validity

The extent to which a method or procedure measures what it is supposed to measure.

Psychometric View

An approach in psychology that focuses on the measurement of mental functions, intelligence, abilities, and attitudes through the use of tests and questionnaires.

Intelligence

The capacity for learning, understanding, and applying knowledge and skills, and the ability to adapt to new situations.

Predictive Validity

The degree to which a score obtained from a test or scale forecasts an individual’s future achievements on a similar activity.