Question

An urn contains 5 red and 2 black balls. Two balls are drawn at random. X denotes number of black balls drawn. What are possible values of X?

Answer 1

The urn contains 5 red and 2 black balls. If two balls are drawn from the urn, it contains either 0 or 1 or 2 black balls.

X can take values 0, 1, 2.

∴ X = {0, 1, 2}.

Answer 2

X denotes the number of black balls drawn.

Sample space of the experiment is

S = {RR, BR, RB, BB}

The value of X corresponding to these outcomes are as follows:

X (RR) = 0

X(BR) = X(RB) = 1

X(BB) = 2

∴ Possible values of X are {0, 1, 2}.