==> \(s = \frac{{{P^2}}}{{2\mu \,g{m^2}}}\) \(s \propto \frac{1}{{{m^2}}}\)
\(\frac{{{s_2}}}{{{s_1}}} = {\left( {\frac{{{m_1}}}{{{m_2}}}} \right)^2} = {\left( {\frac{{200}}{{300}}} \right)^2} = \frac{4}{9} \Rightarrow \,{S_2} = \frac{4}{9} \times 36 = 16\,metres\).