A Population Variable Has a Distribution with a Mean of

question 14

Multiple Choice

A population variable has a distribution with a mean of  = 50 and a variance of ² = 225.From this population a simple random sample of n observations is to be selected and the mean of the sample values calculated.How big must the sample size n be so that the standard deviation of the sample mean is equal to 1.4 (i.e. , = 1.4) ?

• A)n = 11
• B)n = 161
• C)n = 115
• D)n = 36
• E)n = 21

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Definitions:

Developmental Psychologists

Professionals who study the growth and development of the human mind and behavior across the lifespan.

Prenatal Period

The stage of human development that occurs from conception until birth.

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