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The number of ways in which 10 condidate...

The number of ways in which 10 condidates `A_(1),A_(2),......,A_(10)` can be ranked so that `A_(1)` is always above `A_(2)`, is

A

10!

B

`(10!)/(2)`

C

9!

D

None of these

Text Solution

Verified by Experts

The correct Answer is:
B
The candidates can be ranked in 10! Ways. In half of these ways, `A_(1)` is above `A_(2)` and in another halff, `A_(2)` is above `A_(1)`. So, required number of ways `=(10!)/(2)`.
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