Answer
The required solution of probability is, $\frac{1}{2}$
Work Step by Step
If the die is rolled, then 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, thus, $ n\left( S \right)=6$
Also, the event of getting an odd number can be represented by $ E=\left\{ 1,3,5 \right\}$
Since there is only one outcome in this event, therefore, $ n\left( E \right)=3$
Hence, the probability of obtaining an odd number is:
$\begin{align}
& P\left( E \right)=\frac{n\left( E \right)}{n\left( S \right)} \\
& =\frac{3}{6} \\
& =\frac{1}{2}
\end{align}$
