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The numbers 1, 2, 3, ..., n are arrange ...

The numbers 1, 2, 3, ..., `n` are arrange in a random order. The probability that the digits 1, 2, 3, .., `k( k < n)` appear as neighbours in that order is

A

`((n - k) !)/(n !)`

B

`(n - k + 1)/( ""^(n) C_(k))`

C

`(n - k)/(""^(n)C_(k))`

D

`(k!)/(n!)`

Text Solution

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The correct Answer is:
B
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