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There are n locks and n matching keys. E...

There are n locks and n matching keys. Each lock gets opened by only one key which is made for it. Find the maximum number of trials required to open the locks.

A

`n_(c_(2))`

B

`underset(k=2)overset(n)sum (k-1)`

C

`n!`

D

`""^(n+1)C_(2)`

Text Solution

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The correct Answer is:
A, B
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