Find Sample Size

Notes

Notes for Sample Size 1

Notes for Sample Size 2

Notes for Sample Size 3

Notes for Level of Confidence

Practice Problems

\(\textbf{1)}\) Find \(n\) if \( \sigma =7.8\) and error is \(2\) with \(95\%\) confidence interval.


\(\textbf{2)}\) How large should the sample be if you want to do a \(90\%\) confidence level and error is .03 from p and there is no preliminary study.


\(\textbf{3)}\) How large should the sample be if you want to do an \(90\%\) confidence level and width of interval was \(.04\) and prelim study found that \(\hat{p}=.35\)


\(\textbf{4)}\) Find \(n\) if \( \sigma =3\) and error is \(.2\) with \(99\%\) confidence interval.


\(\textbf{5)}\) How large should the sample be if you want to do a \(80\%\) confidence level and error is .02 from p and there is no preliminary study.


\(\textbf{6)}\) How large should the sample be if you want to do an \(95\%\) confidence level and width of interval was \(.16\) and prelim study found that \(\hat{p}=.4\)


See Related Pages\(\)

\(\bullet\text{ Statistics Homepage}\)
\(\,\,\,\,\,\,\,\,\text{All the Best Topics…}\)
\(\bullet\text{ Margin of Error}\)
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\(\bullet\text{ Confidence Intervals}\)
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\(\bullet\text{ Standard Error}\)
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\(\bullet\text{ Confidence Level}\)
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\(\bullet\text{ Type I and Type II Errors}\)
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\(\bullet\text{ One Sample z-test}\)
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\(\bullet\text{ Two Sample z-test for Difference Between Means}\)
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\(\bullet\text{ Hypothesis Test- Difference Between Proportions}\)
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\(\bullet\text{ Chi-squared test}\)
\(\,\,\,\,\,\,\,\,\)



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