SOLUTION
First Part
[tex]\begin{gathered} 4\text{ miles =27 minutes} \\ 1\text{ mile = x } \\ \text{Cross multiply} \end{gathered}[/tex][tex]\begin{gathered} 4x=27\times1 \\ x=\frac{27\times1}{4} \\ x=\frac{27}{4} \\ x=6.75\text{ minutes} \end{gathered}[/tex]Bill will take 6.75 minutes per mile.
Second Part
[tex]\begin{gathered} 10\text{ dollars = 3 hours} \\ 1\text{ dollar = x} \\ \text{Cross multiply} \end{gathered}[/tex][tex]\begin{gathered} 10x=3\times1 \\ x=\frac{3\times1}{10} \\ x=\frac{3}{10} \\ x=0.3 \end{gathered}[/tex]A customer will get 0.3 hours per dollar.
