Solution of problem N1365 Poisson probability theory

Solution of problem N1365 Poisson probability theory

1365. In some areas, on average, for every 100 watermelons grown, one weighs not less than 10 kg. Find the probability that a batch of watermelons from this area containing 400 pieces will: a) exactly 3 watermelons weighing not less than 10 kg each; b) at least three such watermelons.

Additional information:

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