# 50 Followers Problem

If the sum of the terms n, 2n , 3n , of an AP are ${ S }_{ 1 }$, ${ S }_{ 2 }$ and ${ S }_{ 3 }$ then $\frac { { S }_{ 3 } }{ { (S }_{ 2 }-{ S }_{ 1 })\quad \quad }$ is

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