Question

Assume that you want to construct a 95% confidence interval estimate of a population mean. Find an estimate of the sample size needed to obtain the specified margin of error for the 95% confidence interval. The sample standard deviation is given below.

Margin of errors=$6,

standard deviation=$22

The required sample size is __

Answer #1

Standard deviation =$22

Margin of error =E=$6

Level of significance = 1-0.95=0.05

Z critical value is (by using Z table)=1.96

Sample size formula is

=51.65

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