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AP EAMCET202318 May 2023Evening ShiftMathematicsProbabilityActual

If A and B are among 20 persons who sit at random along a round table, then the probability that there are any six persons between A and B is

Options

  1. A1 2
  2. B5 16
  3. C2 19
  4. D2 81

Correct answer

C. 2 19

Step-by-step solution

The no. of ways in which 18 people (excluding A and B ) sit in a round table with 6 people between A & ~B = ¹⁸ C ₆ 2 ! (13-1) ! Thus, probability = 18_ C ₆ 2 ! (13-1) ! 6 ! (20-1) ! = 2 19

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