3999. Of the 25 kinescopes available in a television studio, 5 pcs. produced by plant number 1, 12 pcs. - Plant number 2, and 8 pcs. - Plant number 3. The probability that a kinescope manufactured by factory No. 1 will not fail during the warranty period is 0.95. For a kinescope of plant number 2, this probability is 0.9, and for plant number 3, it is 0.8. Find the probability that at random taken kinescope will withstand the warranty period.

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