A discrete random variable X takes values 10 , 20 , 30 and 40 , with probability 0 . 3 , 0 . 3 , 0 . 2 , 0 .…

A discrete random variable X takes values 10,20,30 and 40, with probability 0.3,0.3,0.2,0.2 respectively. Then the expected value of X is

  1. 12
  2. 22
  3. 23
  4. 24

Solution

Expected value of X is given by ∑XP(X), where P(X) is probability of random variable X.

⇒∑XP(X)=10×0.3+20×0.3+30×0.2+40×0.2

=3+6+6+8=23

Asked in: AP EAMCET 2021 (19 Aug Shift 2)

Practice more Probability questions on Aicharya