A random variable X has the following probability distribution
Then the mean of X is : |
0.3 0.8 0.6 0.7 |
0.8 |
Given probability distribution: $x_i:\ -2,\ -1,\ 0,\ 1,\ 2,\ 3$ $p_i:\ 0.1,\ k,\ 0.2,\ 2k,\ 0.3,\ k$ Sum of probabilities is $1$: $0.1+k+0.2+2k+0.3+k=1$ $0.6+4k=1$ $4k=0.4 \Rightarrow k=0.1$ Mean of $X$: $E(X)=\sum x_ip_i$ $=(-2)(0.1)+(-1)(0.1)+(0)(0.2)+(1)(0.2)+(2)(0.3)+(3)(0.1)$ $=-0.2-0.1+0+0.2+0.6+0.3$ $=0.8$ final answer: mean of $X$ is $0.8$ |