Question

Ten of 16 students in Nyack's class are girls. His teacher selected two helpers by randomly drawing names. He drew a boys name first and then a girls names. Nyack thinks that the probability of this happening is 15/64. Is he correct? If not, Explain his error.

Answer 1

$|\Omega|=16\cdot15=240\\|A|=6\cdot10=60\\\\P(A)=\dfrac{60}{240}=\dfrac{1}{4}$

He's wrong.