Find the Expected Value of a Random Variable X Having

Short Answer

Find the expected value of a random variable X having the following probability distribution: $$\begin{array} { c c c c c } x & 2 & 4 & 6 & 8 \\P ( X = x ) & \frac { 7 } { 20 } & \frac { 2 } { 20 } & \frac { 5 } { 20 } & \frac { 6 } { 20 }\end{array}$$ ​ $$E ( X ) =$$ __________