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Triplets Adam, Bruce, and Charlie enter a triathlon. If there are 9 competitors in the triathlon and medals are awarded for first, second, and third place, what is the probability that at least two of the triplets will win a medal?

User Leighton
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1 Answer

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Answer: Probability that at least two of the triplets will win a medal is19/24

Explanation:

Total number of cmpetitors=9

Total number of selecting 3 winners out of 9 competitors=9C3=84

Number of ways of selecting 2 out of 3 triplets=3C2

Number of selecting 1 out of 6 others =6C1

Number of selecting 2 out of 3 triplet and o1 out of 6 others= 3C2 ×6C1=18

Number of selecting 3 out of 3 triplets=3C3=1

Total ways of selecting less than 2 or 2 triplets= 18+1=19

Probability that at least 2 of the triplets will win is 19/84

User Jaael
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