Решение задачи N4702 теория вероятностей полиномиальный

4702. For each lottery ticket, with probability p1=0.09, a big win can fall, with probability p2=0.21, a small win, and with probability p3=0.7, the ticket can end up without a win. Bought n=14 tickets. Determine the probability of getting n1=1 big wins and n2=3 small ones.

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