3993. 60% of the picture tubes in the warehouse of a television studio are made by plant No. 1, and the rest by plant No. 2. The probability of the fact that the kinescope of factory No. 1 does not fail during the warranty period of service is 0.9, and for the kinescope of factory No. 2 this probability is 0.7. Find the likelihood that at random taken kinescope will withstand the warranty period.
Detailed solution. Decorated in Microsoft Word 2003 (Quest decided to use the formula editor)