[tex]\dfrac{(1\dfrac{3}{5} \cdot (-\dfrac{15}{2} ) )-(2,7\cdot \dfrac{2}{9} )}{3,5\div 3\dfrac{10}{20} + (-7,2)} =[/tex]
[tex]=\dfrac{(\dfrac{8}{5} \cdot (-\dfrac{15}{2} ) )-(\dfrac{27}{10} \cdot \dfrac{2}{9} )}{\dfrac{35}{10} \div \dfrac{70}{20} + (-7,2)} =\dfrac{-12-\dfrac{6}{10} }{\dfrac{35}{10}\cdot \dfrac{20}{70} + (-7,2)}=[/tex]
[tex]=\dfrac{-12,6}{1-7,2} =\dfrac{-12,6}{-6,2} =(-12\dfrac{6}{10} )\div (-6\dfrac{2}{10} )=(-\dfrac{126}{10} )\div (-\dfrac{62}{10} )=(-\dfrac{126}{10} )\cdot (-\dfrac{10}{62} )=\dfrac{126}{62} =\dfrac{63}{31}=2\dfrac{1}{31}[/tex]
