Problem N5645 probability theory confidence interval

Problem N5645 probability theory confidence interval

5645. x̅=26, n=30, σ=4. Find the confidence interval for estimating with reliability γ=0.95 the unknown mathematical expectation m of a normally distributed feature Χ of the general population, if the general standard deviation is σ=4, the sample mean is x̅v=26 and the sample size is n=30

Additional information:

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