To answer this questions we can use the rule of three:
[tex]\begin{gathered} 20\rightarrow\frac{4}{5} \\ x\rightarrow1 \end{gathered}[/tex]Then:
[tex]\begin{gathered} x=\frac{1\cdot20}{\frac{4}{5}} \\ =\frac{20}{\frac{4}{5}} \\ =\frac{5\cdot20}{4} \\ =\frac{100}{4} \\ =25 \end{gathered}[/tex]Therefore, the total lenght of the dirve is 25 miles.
