Solution of problem N4112 probability theory total prob

Solution of problem N4112 probability theory total prob

4112. There are 1000 lamps, 200 belong to the first batch, 300 - to the second batch, 500 - to the third batch. In the first batch of 6%, in the second - 5%, in the third - 4% of defective lamps. One lamp is selected at random. Determine the probability that the selected lamp is defective.

Additional information:

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