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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 the possible values of X?
Solution
5 red + 2 black = 7 balls
X denote the number of black balls drawn.
Sample space of the experiment is
S = {RR, BR, RB, BB}
The value of X corresponding to these out comes are as follow:
X (RR) = 0
X(BR) = X(RB) = 1
X(BB) = 2
∴ Possible values of X are {0, 1, 2}.
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