3632. The assembly receives parts from three machines. The first machine produces 20%, the second - 30%, the third - 50% of parts of this type. The first automatic machine gives 0.2% of marriage, the second - 0.3%, the third - 0.1%. The assembly got a defective part. Find the probability that it is made the first machine.

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