Problem N5577 probability theory confidence interval

Problem N5577 probability theory confidence interval

5577. x̅=21, n=100, σ=12. Determine the confidence interval for estimating with reliability γ=0.975 the unknown mathematical expectation a of the normally distributed feature X of the general population, if the sample mean x̅в=21, the sample size n=100 and the general standard deviation σ=12 are known.

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Detailed solution. Decorated in Microsoft Word 2003 (Quest decided to use the formula editor)