Using Algebra I have concluded that the answer is 12.5 kilometers per liter. :D
First set up your equation
[tex]\frac{8}{100} = \frac{1}{x} \\\\
Next multiply by x
(\frac{8}{100})x = (\frac{1}{x})x \\\\[/tex]
[tex](\frac{8x}{100}) = 1\\\\[/tex]
Then multiply by 100
[tex](\frac{8x}{100}) 100 = (1) 100[/tex]
[tex]8x = 100\\\\
Finally divide by 8
\frac{8x}{8} = \frac{100}{8}[/tex]
[tex]x = 12.5[/tex]
Hope this helps!