Data:
price($)__ gallons
x -------------- 1
18.00 ------------ 4.5
Solving: Rule of three (directly proportional)
[tex] \frac{x}{18.00} = \frac{1}{4.5} [/tex]
multiply cross
[tex]4.5*x = 18.00*1[/tex]
[tex]4.5x = 18.00[/tex]
[tex]x = \frac{18.00}{4.5} [/tex]
[tex]\boxed{\boxed{x = \$\:4.00}}
\end{array}}\qquad\quad\checkmark[/tex]
Answer:
The price in dollars per gallon is $ 4.00