Let x be the number of maximum miles that Tiffany can drive, then we can set the following equation:
![18.95+0.17x=40.](https://img.qammunity.org/2023/formulas/mathematics/high-school/7y9ip857hxnxxfpwisw4eh8acswjd01zkh.png)
Subtracting 18.95 from the above equation we get:
![\begin{gathered} 0.17x=40-18.95, \\ 0.17x=21.05. \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/high-school/7uwyv6mw2qefezd59q5wekk5lqt384o520.png)
Dividing by 0.17 we get:
![x=(21.05)/(0.17)=123.8235294.](https://img.qammunity.org/2023/formulas/mathematics/high-school/cebbfuroisveokq2pkbz3445xs1m9bglir.png)
Now, since the cost is for each mile, then we have to round to the nearest lowest whole number, therefore, she can drive for 123 miles.
Answer: 123 miles.