Question

A class consists of $100$ students, $25$ of them are girls and $75$ boys, $20$ of them are rich and remaining poor, $40$ of them are fair complexioned. The Probability of selecting a fair complexioned rich girl is

Answer 1

$n\left(A\right)=25$, $n\left(B\right)=75,n\left(C\right)=20,n\left(D\right)=80,n\left(E\right)=40,n\left(F\right)=60$

$P\left(A\right)=\frac{25}{100}=\frac{1}{4};P\left(B\right)=\frac{3}{4};P\left(C\right)=\frac{1}{5};P\left(E\right)=\frac{2}{5}$

$P(A\cap E\cap C)=\frac{1}{4}\times \frac{2}{5}\times \frac{1}{5}=\frac{1}{50}$