[tex] 2\frac{3}{5} +1 \frac{2}{5} - \frac{4}{9} : \frac{18}{4} = \\= \frac{2*5+3}{5} + \frac{1*5+2}{5} - \frac{4}{9} * \frac{4}{18} \\ = \frac{13}{5} + \frac{7}{5} - \frac{16}{162} \\ = \frac{20}{5} - \frac{16}{162} \\ = \frac{3240-16*5}{162*5} \\ = \frac{3160}{810} \\ = \frac{316}{81} \\ [/tex]
