In a box containing 15 apples, exactly 6 apples are rotten. Each day one apple is taken out from the box. What is the probability that after four days there are exactly 8 apples in the box that are not rotten?

out of 15 apples 9 are good and 6 are rotten. after 4 days 8 apples are good means 1 good and 3 rotten apple must be taken out of the box. so the probability:= n(E)/n(S) (9c1)*(6c3)/15c4 =9*20/1365 =12/91

if this is the probability that means out of 15 apples 9 are good and 6 are rotten. after 4 days 8 apples are good means 1 good and 3 rotten apple must be taken out of the box. so the probability: (9c1)*(6c3) =9*20 =180 and if the answer is correct so mark it as best.

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