Solution:
According to the question,
\[\begin{gathered}
\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,{\text{Acid}}\,\,\,\,\,\,\,\,\,\,\,\,\,{\text{Water}}\,\,\,\,\,\,{\text{Total}} \hfill \\
\left. \begin{gathered}
{\text{Sample I}}\,\,\,\,\,\,\,\,{{\text{2}}_{ \times 40}} = 80\,\,\,\,:\,\,\,\,{1_{ \times 40}} = 40\,\,\,\,\,\,{3_{ \times 40}} \hfill \\
\hfill \\
{\text{Sample II}}\,\,\,\,\,\,{3_{ \times 24}} = 72\,\,\,\,\,:\,\,\,\,{2_{ \times 24}} = 48\,\,\,\,{5_{ \times 24}} \hfill \\
\hfill \\
{\text{Sample III}}\,\,\,\,\,\underline {{5_{ \times 15}} = 75} \,\,\,\,:\,\,\,\,\,\underline {{3_{ \times 15}} = 45} \,\,\,\,{8_{ \times 15}} \hfill \\
\end{gathered} \right]120 \hfill \\
\end{gathered} \]
\[{\text{Ratio of quantity }}\boxed{\,\,\,227\,\,\,\,\,:\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,133\,\,\,}\]
$${\text{Required ratio = }}133:227$$