A sample of 25 elements from a normally distributed population is selected.the sample mean is 10.assuming a population standard deviationog 4, determine the 95%confidence interval for mean ?

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$95\%CI=(\bar x-z_{0.025}\frac{s}{\sqrt{n}},\bar x+z_{0.025}\frac{s}{\sqrt{n}})=$

$=(10-1.96\frac{4}{\sqrt{25}},10+1.96\frac{4}{\sqrt{25}})=(8.432,11.568).$

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Question ID: mtid-4-stid-47-sqid-4282-qpid-2