Question

Let $U$ be universal set of all the students of class $XI$ of a co-educational school and $A$ be the set of all girls in class $XI$. Find $A^{\prime }$.

Answer 1

In a co-educational school, there can be boys and girls.
$A$ is the set of all girls.
$\because A^{\prime }=U-A$
$\therefore A^{\prime }=$ Set of all students - Set of all girls
$\Rightarrow A^{\prime }=$ Set of all boys in class XI.