Question

Let $A=\{1,3,5,7\}$ and $B=\{2,4,6,8\}$ be two sets and $R$ be a relation from $A$ to $B$ defined by the phrase ${}^{\prime \prime }(x,y)\in R:x<y^{\prime \prime },$ then the number of elements in the range of $R$ is

Answer 1

$R=\left\{\right(1,2),(1,4),(1,6),(1,8),(3,4),(3,6),(3,8),(5,6),(5,8),(7,8\left)\right\}$
$\therefore$ Range $=\{2,4,6,8\}$
No. of elements $=4$