[tex]\dfrac{1\dfrac{4}{5}-\dfrac{1}{3}}{2\dfrac{2}{5}}=\left(1\dfrac{4\cdot3}{5\cdot3}-\dfrac{1\cdot5}{3\cdot5}\right):\left(2\dfrac{2}{5}\right)=\left(1\dfrac{12}{15}-\dfrac{5}{15}\right):\dfrac{2\cdot5+2}{5}\\\\=1\dfrac{12-5}{15}:\dfrac{12}{5}=1\dfrac{7}{15}\cdot\dfrac{5}{12}=\dfrac{1\cdot15+7}{15}\cdot\dfrac{5}{12}=\dfrac{22}{15}\cdot\dfrac{5}{12}=\dfrac{11}{3}\cdot\dfrac{1}{6}\\\\=\dfrac{11}{18}[/tex]