5728. Workers of a mechanical plant are examined. Find the minimum sample size at which, with a reliability of 0.975, the accuracy of estimating the average monthly wage of factory workers based on the sample mean is δ=0.3, if its square deviation is known to be σ=2 rubles. It is assumed that the monthly salary is a random variable distributed according to the normal law.

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