What Sample Size Is Needed to Estimate a Population Mean

question 82

Multiple Choice

What sample size is needed to estimate a population mean within ±50 of the true mean value using a confidence level of 95%, if the true population variance is known to be 122,500?

• A) 211
• B) 155
• C) 214
• D) 189

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Definitions:

Overall Motivation

The combined internal drive and external influences that energize, direct, and sustain an individual's efforts toward achieving a goal.

Trust

Confidence in the honesty, integrity, reliability, and fairness of a person or system.

Major Institutions

Key established organizations or foundations, especially those influential in society, like schools, hospitals, or banks.

Decreased Substantially

Reduced in size, amount, or extent by a large margin.