The sample standard deviation is given by:
[tex]s=\sqrt[]{\frac{1}{N}\sum^N_{i=1}(x_i-\bar{x})^2}[/tex]Where:
[tex]\begin{gathered} \bar{x}=\frac{514+507+502+497+495+506+458+478+463+513}{10} \\ \bar{x}=493.3 \end{gathered}[/tex]Therefore:
[tex]\begin{gathered} s=\sqrt[]{\frac{1}{10}\sum ^{10}_{i=1}(x_i-493.3)^2} \\ s\approx20.155 \end{gathered}[/tex]