Đáp án:
$\begin{array}{l}
e)\left( {0,75 - 0,6 + \dfrac{3}{7} + \dfrac{3}{{13}}} \right):\left( {\dfrac{{11}}{7} + \dfrac{{11}}{{13}} + 2,75 - 2,2} \right)\\
= \left( {0,15 + \dfrac{3}{7} + \dfrac{3}{{13}}} \right):\left( {\dfrac{{11}}{7} + \dfrac{{11}}{{13}} + 0,55} \right)\\
= \left( {\dfrac{3}{{20}} + \dfrac{3}{7} + \dfrac{3}{{13}}} \right):\left( {\dfrac{{11}}{7} + \dfrac{{11}}{{13}} + \dfrac{{11}}{{20}}} \right)\\
= 3.\left( {\dfrac{1}{{20}} + \dfrac{1}{{70}} + \dfrac{1}{{13}}} \right):\left( {11.\left( {\dfrac{1}{7} + \dfrac{1}{{13}} + \dfrac{1}{{20}}} \right)} \right)\\
= \dfrac{3}{{11}}\\
f)\left( {\dfrac{{10\sqrt {1,21} }}{7} + \dfrac{{22\sqrt {0,25} }}{3}} \right):\left( {\dfrac{5}{{\sqrt {49} }} + \dfrac{{\sqrt {225} }}{9}} \right)\\
= \left( {\dfrac{{10.1,1}}{7} + \dfrac{{22.0,5}}{3}} \right):\left( {\dfrac{5}{7} + \dfrac{{15}}{9}} \right)\\
= \left( {\dfrac{{11}}{7} + \dfrac{{11}}{3}} \right):\left( {\dfrac{5}{7} + \dfrac{5}{3}} \right)\\
= 11.\left( {\dfrac{1}{7} + \dfrac{1}{3}} \right):\left( {5.\left( {\dfrac{1}{7} + \dfrac{1}{3}} \right)} \right)\\
= \dfrac{{11}}{5}
\end{array}$
