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In a class, there are n students including the students P and Q. What is the probability that P and Q sit together if seats are assigned randomly?

Options

  1. A1 n
  2. B2 n
  3. C4 n
  4. D1 2 n

Correct answer

B. 2 n

Step-by-step solution

The number of ways in which p and q seat together =( n -1)! 2 So, required Probability = 2(n-1)! n! = 2 n

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