A Study Is Going to Be Conducted in Which a Mean

question 80

Multiple Choice

A study is going to be conducted in which a mean of a lifetime of batteries produced by a certain method will be estimated using a 90% confidence interval.The estimate needs to be within +/- 2 hours of the actual population mean.The population standard deviation is estimated to be around 25.The necessary sample size should be at least _______.

• A) 100
• B) 21
• C) 923
• D) 35
• E) 423

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Definitions:

Disjunctive Syllogism

An argument based on deductive reasoning that uses elimination to present just two options in its premises.

Sound

Vibrations that travel through the air or another medium and can be heard when they reach a person's or animal's ear.

Perfectly Flat

Describing a surface that is completely smooth and level, without any bumps, curves, or inclines.

Valid

In logic, refers to an argument where, if the premises are true, the conclusion must also be true.