4651. On three automatic machines, parts of the same type were made in the amount of 2000, 1700 and 900 pieces, respectively. Marriage in the production of machine tools is 0.5%, 0.2 and 1%, respectively. A part taken at random turned out to be defective. Find the probability that it was made on the second machine.

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