If .^(n)C(r )=84, .^(n)C(r-1)=36 " and" ...

If `.^(n)C_(r )=84, .^(n)C_(r-1)=36 " and" .^(n)C_(r+1)=126`, then find the value of n.

A

n=8,r=4

B

n=9,r=3

C

n=7,r=5

D

none of these

Verified by Experts

The correct Answer is:

B

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