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Five persons A, B, C, D and E are in queue of a shop. The probability that A and E are always. together, is

Options

  1. A1 4
  2. B2 3
  3. C2 5
  4. D3 5

Correct answer

C. 2 5

Step-by-step solution

The total number of ways to arrange 5 persons in a queue is 5! = 120 . To find the number of favorable outcomes where A and E are always together, treat (AE) as a single unit. Now, we have 4 units to arrange: (AE), B, C, D . The number of ways to arrange these 4 units is 4! = 24 . Within the unit (AE) , A and E can be arranged in 2! = 2 ways ( AE or EA ). Therefore, the total number of favorable arrangements is 24 2 = 48 . The probability is given by Favorable outcomes Total outcomes = 48 120 . Simplifying the frac

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