Problem N5550 probability theory confidence interval

Problem N5550 probability theory confidence interval

5550. x̅=20.11, n=64, σ=1. Given the general standard deviation σ=1 of a normally distributed random variable X of the general population, the sample mean x̅v=20.11 sample size n=64. Find the confidence interval for estimating the unknown mathematical expectation a with a given reliability γ=0.95.

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