Задача N5390 теория вероятностей доверительный интервал

5390. x̅=84.25, n=121, σ=11. Find confidence intervals for estimating the mathematical expectation a of a normal distribution with a reliability of 0.95, knowing the sample mean x̅=84.25, the sample size (number of observations) n=121, and the standard deviation σ=11.

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