Answer
Sample variance = $s^{2}=17.3$
Sample standard deviation = $s =4.16$
Work Step by Step
Recall the shortcut formula for calculating the variance ($s^{2}$)$:$
$$s^{2}=\frac{\sum x_{i}^{2}-\frac{(\sum x_{i})^{2}}{n}}{n-1}$$
Let's create a table in which we compute $\displaystyle \sum x_{i}$ and $\displaystyle \sum x_{i}^{2}.$
$$ \begin{array}{rrr}
& x & x^{2}\\
\hline & 3 & 9\\
& 1 & 1\\
& 10 & 100\\
& 10 & 100\\
& 4 & 16\\
\hline\rm Sum &28 & 226
\end{array}$$
Plug in the given values (there are $n=5$ data items):
$$\begin{align*}
s^{2}&= \displaystyle \frac{226-\frac{(28)^{2}}{5}}{5-1} & & \\
& =17.3 \\\\
s&= \sqrt{17.3} =4.16
\end{align*} $$
