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Chapter 9: Q.11.47 (page 460)

A sample size that will ensure a margin of error of at most the one specified.

Short Answer

Expert verified

The required sample size is 1, 842

Step by step solution

01

Given information

Margin of error =.03, confidence level =99%

02

calculation

When the margin of error is 0.03 and the confidence level is 99%, calculate the sample size.

With a 99% confidence level, the required value of zα/2from table areas under the standard normal curve is 2.575.

Use p'g=0.5 because the value in the range closet to 0.5.

The sample size is,

n=0.25(zaE)2=0.25(2.5750.03)2=0.25(7,367.361)=1,841.84≈1842

The required sample size is 1,842

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