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Interview Question

Assistant Trader Intern Interview(Student Candidate) Bala Cynwyd, PA

Five guys, all of different ages enter a bar and take a

  seat at a round table. What is the probability that they are seated in ascending order of age? (clockwise or counter-clockwise)
Answer

Interview Answer

2 Answers

1

5! or 120 total seating positions. 5 possible starting positions because the table is round. 2 possible directions.

This makes 10 arrangements that fulfill the prompt, ie P = 10/5! = 1/12

Interview Candidate on 18/02/2011
1

Make the youngest person a fixed point. The second youngest can sit on 2 seats in 4 remaining seats (left or right of the youngest). The third youngest can sit on 1 seat in the 3 remaining because we defined ordered by previous step. Fourth youngest can sit on 1/2. Last person 1/1

2/4*1/3*1/2=1/12

Anonymous on 09/11/2011

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