Решение задачи N3474 теория вероятностей Бернулли

3474. 8 independent tests have been carried out, each of which consists of simultaneously throwing up two coins. Find the probability that a) in three trials of the eight appear on the 2 coat of arms; b) two coats of arms will fall out at least two times.

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