Solution of problem N3934 probability theory total prob

Solution of problem N3934 probability theory total prob

3934. Watches of the same brand are made in three factories and arrive at the store. The first plant produces 20% of all products, the second - 30%, the third - 50%. In the production of the first plant, 5% of all hours are in a hurry, the second - 3%, the third - 2%. What is the probability that the watches bought in the store are in a hurry?

Additional information:

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