Question

The probability distribution of a random variable X is given below:

$\begin{array}{ccccc}X=x& 0& 1& 2& 3\\ P(X-x)& \frac{1}{10}& \frac{2}{10}& \frac{3}{10}& \frac{4}{10}\end{array}$

Then the variance of X is

• A. 1
• B. 2
• C. 3
• D. 4

Answer 1

The correct option is A

1

$\text{Mean}\mu =2{\sigma }^2+{\mu }^2=5\Rightarrow {\sigma }^2=1$