The slope can be found by the "rise over run", that is, is the change in variable y divided by the change in variable x.
In this question,
[tex]\begin{gathered} slope=\frac{rise\text{ in the road}}{run\text{ in highway}} \\ \end{gathered}[/tex]Substituting the values:
[tex]\begin{gathered} slope=\frac{30}{483} \\ slope=0.06\text{ feet per feet of highway.} \end{gathered}[/tex]Answer: 0.06 feet per feet of highway.
