# A Random Variable X Has the Following Probability Distribution - Mathematics and Statistics

MCQ

A random variable X has the following probability distribution:

then E(X)=....................

• 0.8

• 0.9

• 0.7

• 1.1

#### Solution

(a) 0.8

 X = x -2 -1 0 1 2 3 P(x) 0.1 0.1 0.2 0.2 0.3 0.1

E(X)=sumx_iP(x_i)

=( -2) x 0.1 + ( -1) x 0.1+ 0 x 0.2 +1x 0.2+ 2 x 0.3 + 3 x 0.1

= - 0.2 - 0.1 + 0 + 0.2 + 0.6 + 0.3

=0.8

Concept: Random Variables and Its Probability Distributions
Is there an error in this question or solution?