#### Answer

The required solution of probability is, $\frac{1}{6}$

#### Work Step by Step

We know that when the die is rolled, the sample space of equally likely outcomes is $ S=\left\{ 1,2,3,4,5,6 \right\}$
As there are six outcomes in the sample space, therefore, $ n\left( S \right)=6$
So, the event of getting a 4 can be represented by $ E=\left\{ 4 \right\}$
Since there is only one outcomes in this event, therefore, $ n\left( E \right)=1$
Thus, the probability of getting a 4 is given below:
$\begin{align}
& P\left( E \right)=\frac{n\left( E \right)}{n\left( S \right)} \\
& =\frac{1}{6}
\end{align}$