For the following probability distribution determine standard deviation of the random variable X.

Explanation

We have,

We know that, standard deviation of X=`sqrt(VarX)`
where, VarX=`E=(X^(2))-[E(X)]^(2)`
`therefore Var X=[0.8+4.5+4.8]-[0.4+1.5+1.2]^(2)`
`=10.1-(3.1)^(2)=10.01-9.61=0.49`
`therefore` Standard deviation of X =`sqrt(Var X)=sqrt(0.49)=0.7`