JEE Main 2023 (Online) 11th April Evening ShiftQuestion 1
Let $A=\{1,3,4,6,9\}$ and $B=\{2,4,5,8,10\}$. Let $R$ be a relation defined on $A\times B$ such that $R=\{((a_1,b_1),(a_2,b_2)):a_1\le b_2\text{ and }b_1\le a_2\}$. Then the number of elements in the set $R$ is
Sets, Relations and Function
Solution
Pairs $(a_1,b_1),(a_2,b_2)$ with $a_1\le b_2$ and $b_1\le a_2$; enumerating over the 25 elements of $A\times B$ gives 160. Option (C).