$\"\"$

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The total number of residents are $\"\"$ .

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The average commuting time to work is $\"\"$ .

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The standard deviation is $\"\"$ .

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Find the maximum error of estimate for a $\"\"$ confidence level.

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In a $\"\"$ confidence interval, $\"\"$ of the area lies in tail.

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The corresponding $\"\"$ value is $\"\"$ .

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Formula for maximumu error estimate is $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$

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Find the confidence interval.

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The confidence interval CI for a population mean $\"\"$ is $\"\"$ .

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Substitute $\"\"$ and $\"\"$ .

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$\"\"$ .

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$\"\"$ .

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The confidence interval is $\"\"$ .

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$\"\"$

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$\"\"$ .

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The confidence interval is $\"\"$ .