5410. x̅=18.31, n=49, σ=9. Given the standard deviation σ=9 of a normally distributed random variable X, sample mean x̅=18.31, sample size n=49. Find confidence intervals for estimating the unknown mathematical expectation a with a given reliability γ=0.95.

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