# GATE2015-40

For a discrete random variable $X$, $\textit{ran}(X)=\{0,1,2,3\}$ and the cumulative probability $F(X )$ is shown below: $$\begin{array}{|c|c|c|c|c|} \hline X & 0 & 1 & 2 & 3 \\ \hline F(X) & 0.5 & 0.6 & 0.8 & 1.0 \\ \hline \end{array}$$The mean value of $X$ is ___________