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If ""^nCr-84,""^nC(r-1)=36 and ""^nC(r+1...

If `""^nC_r-84,""^nC_(r-1)=36 and ""^nC_(r+1)=126` , then n equals :

A

8

B

9

C

10

D

5

Text Solution

Verified by Experts

The correct Answer is:
B
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