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Suppose a sample of 523 suspected criminals is drawn. Of these people, 141 were captured. Using the data, construct a 95% confidence interval for the population proportion of people who are captured after appearing on the 10 most wanted list. Round your answers to three decimal places.

Suppose a sample of 523 suspected criminals is drawn. Of these people, 141 were captured-example-1

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To solve this problem we use the following formula:


p\pm z\cdot\sqrt{(p(1-p))/(n)}

Where:

p: proportion of the population

n: sample

z: This is the value given by the % of confidence and the normal distribution

First, we identify the variables of the problem:

n = 523

d = 141

alpha = (1-%confidence)/2

Second, we find the values of p and z:


\begin{gathered} p=(d)/(n)=(141)/(523) \\ \\ 1-p=(382)/(523) \end{gathered}

And for Z, we find the value of B such that:


P(ZUsing excel, we can see that<strong> B = 1.96</strong><p><strong>Finally, we replace these values with the formula:</strong></p>[tex](141)/(523)\pm1.96\sqrt{(141)/(523)\cdot(382)/(523)(1)/(523)}

As result, we get that:


0.270\pm0.038

And the inferior limit is equal to 0.232 and the superior limit is equal to 0.308

User Benjaminplanche
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