question_answer 45)

An urn contains 5 red and 2 black balls. Two balls are randomly drawn. Let X represent the number of black balls. What are the possible values of X ? is X a random variable ? 

Answer:

We have 5 red and 2 black balls. When 2 balls are drawn at random, then there are the following possibilities. (i) Both balls drawn are red. (ii) 1 red and 1 black ball. (iii) Both black balls In case (i), X = 0 In case (ii), X = 1 In case (iii), X = 2 Therefore x is a random variable and x may take the value 0, 1, 2.