Answer
The required probability is, $\frac{3}{13}$
Work Step by Step
Note that with 52 cards in the deck, the total number of possible ways in which a single card is dealt is 52.
Therefore, the total number of possible outcomes in the sample space is 52, $ n\left( S \right)=52$
Assume $ E $ to be the event of being dealt a picture card; then clearly $ n\left( E \right)=12$
Thus, the probability of being dealt a picture card is:
$\begin{align}
& P\left( E \right)=\frac{n\left( E \right)}{n\left( S \right)} \\
& =\frac{12}{52} \\
& =\frac{3}{13}
\end{align}$
