To find the unit rate of miles per gallon, you can use the formula:
\[ \text{Unit Rate} = \frac{\text{Total Miles}}{\text{Total Gallons}} \]
Given that Valerie can drive 288 miles on a full tank of gas that holds 16 gallons, we can substitute these values into the formula:
\[ \text{Unit Rate} = \frac{288 \text{ miles}}{16 \text{ gallons}} = 18 \text{ miles per gallon} \]
So, the unit rate is 18 miles per gallon.