[tex]\displaystyle \\
\frac{2}{4} = \frac{2\times 25}{4 \times 25} =\frac{50}{100} = \boxed{50\% } \\ \\ \\
0,3 = \frac{3}{10} = \frac{3\times 10}{10 \times 10} =\frac{30}{100} = \boxed{30\% } \\ \\ \\
\frac{4}{5} = \frac{4\times 20}{5 \times 20} =\frac{80}{100} = \boxed{80\% } \\ \\ \\
\frac{1}{5} = \frac{1\times 20}{5 \times 20} =\frac{20}{100} = \boxed{20\% } \\ \\ \\ [/tex]
