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If \ ^(43)C(r-6)=\ ^(43)C(3r+1)\ then t...

If `\ ^(43)C_(r-6)=\ ^(43)C_(3r+1)\ ` then the value of `r` is `12` b. `8` c. `6` d. 10 e. 14

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`r-6+3 r+1=43
[therefore n_{C_x}=n_{C_y} Rightarrow n= x+y ` or ` x=y]`
`Rightarrow 4 r-5=43`
`Rightarrow 4 r=48`
`Rightarrow r=12`
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