To find the cost per gallon when given a total cost and the number of gallons, follow these steps:
1. Identify the total cost: [tex]$\$[/tex]4.50[tex]$.
2. Identify the total number of gallons: $[/tex]2[tex]$ gallons.
3. To determine the cost per gallon, divide the total cost by the total number of gallons.
Mathematically, this can be expressed as:
\[
\text{Cost per gallon} = \frac{\text{Total cost}}{\text{Total gallons}}
\]
Substituting in the given values:
\[
\text{Cost per gallon} = \frac{4.50}{2}
\]
4. Perform the division:
\[
\text{Cost per gallon} = 2.25
\]
Therefore, the cost per gallon is $[/tex]\[tex]$2.25$[/tex].