[tex]3\frac{1\cdot15}{4\cdot15}+2\frac{2\cdot12}{5\cdot12}-(4\frac{1\cdot20}{3\cdot20}-2\frac{2\cdot20}{3\cdot20})=\\\\=3\frac{15}{60}+2\frac{24}{60}-4\frac{20}{60}+2\frac{40}{60}=\\\\=5\frac{39}{60}-4\frac{20}{60}+2\frac{40}{60}=\\\\=1\frac{19}{60}+2\frac{40}{60}=\\\\=\boxed{3\frac{59}{60}}[/tex]
