[tex]C_{10,4}\cdot C_{5,2}=\\\\\\\frac{10!}{(10-4)!4!}\cdot\frac{5!}{(5-2)!2!}=\\\\\\\frac{10\cdot9\cdot8\cdot7\cdot6!}{6!4!}\cdot\frac{5\cdot4\cdot3!}{3!2!}=\\\\\\\frac{10\cdot9\cdot8\cdot7}{4\cdot3\cdot2\cdot1}\cdot\frac{5\cdot4}{2\cdot1}=\\\\\\210\cdot10=\\\\\boxed{2100}[/tex]
Obs.: Considerando alunos = menino + menina, encontra-se 50 como resposta - aplicando raciocínio análogo.
