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MHT CET202123 Sep 2021Evening ShiftMathematicsProbabilityActual

Rooms in a hotel are numbered from 1 to 19 . Rooms are allocated at random as guests arrive. The first guest to arrive is given a room which is a prime number. The probability that the second guest to arrive is given a room which is a prime number is

Options

  1. A8 19 7 18
  2. B8 19
  3. C8 19 7 19
  4. D7 18

Correct answer

D. 7 18

Step-by-step solution

Prime numbers from 1 to 19 are 2,3,5,7,11,13,17,19 i.e. 8 such numbers. The room with prime number is given to the first guest. The probability that second guest will get a room with prime number = 7 18 .

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