To answer this question we have to divide the total cost of the gallons by the total number of gallons, and that will give us the unit price per gallon.
Dividing the total cost by the number of gallons we get:
[tex]\frac{17.84}{4.5},[/tex]simplifying the above fraction we get:
[tex]\frac{17.84}{4.5}\approx3.96.[/tex]Answer: The unit price in dollars is:
[tex]3.96[/tex]