Решение задачи N3902 теория вероятностей полная вероятн

3902. In the box there are parts of 3 types. Of these, 30-first 20-second and 50-third. Among the parts of the first type 20% painted, the second type 30%, the third type 40%. Find the probability that the extracted part is painted for good luck.

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