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    Question

    A box contains 13 black and 13 white balls. The probability of drawing two balls of the same color is?

    A 151/260 Correct Answer Incorrect Answer
    B 145/272 Correct Answer Incorrect Answer
    C 161/292 Correct Answer Incorrect Answer
    D 156/325 Correct Answer Incorrect Answer
    E None of these Correct Answer Incorrect Answer

    Solution

    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 = `(26xx25)/(2xx1)` = 325 Let E= event of drawing 2 balls of the same color n (E) = 13C 2 + 13C2 = [if gte msEquation 12]> 13 × 12 2 × 1 [if !msEquation]--> [endif]-->`(13xx12)/(2xx1) + (13xx12)/(2xx1)` = 78 +78 = 156 [if gte msEquation 12]>∴ [if !msEquation]--> [endif]-->P (E) = [if gte msEquation 12]> n ( E ) n ( S ) [if !msEquation]--> [endif]-->`(n(E))/(n(S) )= 156/325`

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