Question

A function is defined from $A$ to $B,$ where number of elements in $A$ and $B$ are $2$ and $6$ respectively. If the total number of functions is $x$ and total number of one one functions is $y,$ then the value of $x+y$ is

Answer 1

We have $n\left(A\right)=2$ and $n\left(B\right)=6;$
So, total number of functions $=6^2=36$
Total number of one one functions $=6\times 5=30$
So, clearly the values of $x$ and $y$ are $36$ and $30$ respectively.
Thus $x+y=66$