Đáp án:
$\begin{array}{l}
\left( {\frac{9}{{25}} - 2.18} \right):\left( {3\frac{4}{5} + 0,2} \right)\\
= \left( {\frac{9}{{25}} - 36} \right):\left( {\frac{{3.5 + 4}}{5} + \frac{1}{5}} \right)\\
= \frac{{9 - 25.36}}{{36}}:\left( {\frac{{19 + 1}}{5}} \right)\\
= \frac{{9 - 900}}{{36}}:4\\
= \frac{{ - 891}}{{36.4}}\\
= \frac{{ - 891}}{{144}}\\
= \frac{{99}}{{16}}
\end{array}$
