S1 : Twice the weight of Sohan is less than the weight of Mohan or that of Rohan.

S2 : Twice the weight of Rohan is greater than the weight of Mohan or that of Sohan.

Question: Which one of the following statements is correct?

The correct option is Weight of Sohan is least.

Let us represent the weights of Sohan, Mohan, and Rohan by variables $S$, $M$, and $R$ respectively. Since weight is a physical quantity, $S>0$, $M>0$, and $R>0$.

First, let us analyze statement S1:
"Twice the weight of Sohan is less than the weight of Mohan or that of Rohan."
This statement implies that twice the weight of Sohan is less than the weight of Mohan, and it is also less than the weight of Rohan. Mathematically, we can express this as two inequalities:
1) $2S<M$
2) $2S<R$

From inequality (1), since $S>0$, we have:
$S<2S<M\Rightarrow S<M$

From inequality (2), similarly, we have:
$S<2S<R\Rightarrow S<R$

Combining these, we get:
$S<M$ and $S<R$

This shows that Sohan's weight ($S$) is strictly less than Mohan's weight ($M$) and also strictly less than Rohan's weight ($R$). Therefore, Sohan must have the least weight among the three.