It took one-fourth of a gallon of gas to dive my vesper 3 1/2 miles,How much gas will it take to drive one mile

\(\frac{0.25\text{ gallons}}{3.5 \text{ miles}}=\frac{0.25/3.5\text{ gallons}}{3.5/3.5\text{ miles}} \approx \frac{1/14\text{ gallons}}{1\text{ mile}}\)

It will take 1/14 of a gallon to drive one mile.