Calculate the Standard Deviation of X for the Probability Distribution

Short Answer

Calculate the standard deviation of X for the probability distribution. Round your answer to two decimal places if necessary. $$\begin{array} { | c | c | c | c | c | c | c | } \hline x & - 19 & - 15 & 3 & 13 & 22 & 30 \\\hline P ( X = x ) & 0.2 & 0.1 & 0.1 & 0.1 & 0 & 0.5 \\\hline\end{array}$$ ​ $$\sigma =$$ __________