Решение задачи N2507 теория вероятностей

2507. Among 25 students, of which 15 girls play 4 theater tickets, and everyone can win only one ticket. What is the probability that among the ticket holders there will be: a) three young men and one girl; b) at least one young man?

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