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Given that n is the odd the number of wa...

Given that n is the odd the number of ways in which three numbers in A.P. can be selected from {1,2,3,4….,n} is

A

`(n-1)^2/2`

B

`(n+1)^2/4`

C

`(n+1)^2/2`

D

`(n-1)^2/4`

Text Solution

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The correct Answer is:
D
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