question_answer 1)

State which of the following are not the probability distributions of a random variable. Give reasons for your answer.       (i)       (ii)       (iii)       (iv)   

Answer:

 (i) Sum of probabilities             is a probability distribution. (ii)    Here P(x = 3) = ?0.1 Which is imposible, since therefore, is not a probability distribution. (iii)   Sum of probabilities + 0.2 = 0.9 is not a probability distribution (iv)  Sum of probabilities = + 0.4 + .1 + 0.05 = 1.05   is not a probability distribution