Question

A brother and a sister are in the same math class. There are 8 boys and 10 girls in the class. One boy and one girl are randomly chosen. What is the probability that the brother and sister are chosen? Write your answer as a fraction in simplest form.

Answer 1

$|\Omega|=8\cdot10=80\\ |A|=1\\\\ P(A)=\dfrac{1}{80}$