Question
A box contains 13 black and 13 white balls. The
probability of drawing two balls of the same color is? Â ÂSolution
Total number of balls = 13 + 13 = 26 Let S be the sample space. Then, n (S) = number of ways of drawing 2 balls out of 26 = 26 C 2 Â = 
= 325 Let E= event of drawing 2 balls of the same color n (E) = 13C 2 + 13C2Â = Â = 78 +78 = 156 Â P (E) = Â Â or (12/25)
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