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If ^n Pr=^n P(r+1)a n d^n Cr=^n C(r-1,) ...

If `^n P_r=^n P_(r+1)a n d^n C_r=^n C_(r-1,)` then the value of `n+r` is.

A

2

B

3

C

4

D

5

Text Solution

Verified by Experts

The correct Answer is:
B
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