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A research institute poll asked respondents if they felt vulnerable to identity theft. In the poll, n=1086 and x=571 who said "yes." Use a 99% confidence level. A) Construct the confidence interval._ < p <_ (round to three decimal places.)

A research institute poll asked respondents if they felt vulnerable to identity theft-example-1
User Rooney
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1 Answer

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The given information is:

n=1086

x=571

Confidence level 99%

First, we need to find the sample proportion. It is given by the formula:


\hat{p}=(x)/(n)

By replacing the known values, we obtain:


\hat{p}=(571)/(1086)=0.526

Now, the confidence interval is given by:


\begin{gathered} \hat{p}-E<p>Where z* is the z-value for the confidence level. As the C.L=99%, then z is:</p>[tex]\begin{gathered} z^*_{(\alpha)/(2)}\rightarrow(\alpha)/(2)=0.99+(1-0.99)/(2)=0.99+(0.01)/(2)=0.995 \\ \\ And\text{ z for 0.995 is} \\ z^*=2.576 \end{gathered}

Now, replace this value into the formula and solve:


\begin{gathered} E=2.576\sqrt{(0.526(1-0.526))/(1086)} \\ \\ E=2.576\sqrt{(0.249)/(1086)} \\ \\ E=2.576√(0.0002) \\ \\ E=2.576*0.015 \\ \\ E=0.039 \end{gathered}

The confidence interval is then:

[tex]\begin{gathered} 0.526-0.039

The answer is above.

User Avimehenwal
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