Two friends, Grayson and Santiago, had just bought their first cars. The equation \( y=31.9 x \) represents the number of miles, \( y \), that Santiago can drive his car for every \( x \) gallons of gas. Grayson uses 8 gallons of gas to drive 328.8 miles in his car. How many miles less does Santiago's car travel on one gallon of gas than Grayson's car?

To determine how many miles less Santiago's car travels on one gallon of gas compared to Grayson's car, follow these steps: 1. **Calculate Santiago's Mileage:** The equation given is \( y = 31.9x \), where \( y \) is the number of miles and \( x \) is the number of gallons. This means Santiago's car travels **31.9 miles per gallon**. 2. **Calculate Grayson's Mileage:** Grayson uses 8 gallons of gas to drive 328.8 miles. \[ \text{Mileage} = \frac{\text{Total Miles}}{\text{Gallons Used}} = \frac{328.8}{8} = 41.1 \text{ miles per gallon} \] 3. **Determine the Difference:** Subtract Santiago's mileage from Grayson's mileage to find the difference per gallon. \[ 41.1 \text{ mpg} - 31.9 \text{ mpg} = 9.2 \text{ miles per gallon} \] **Conclusion:** Santiago's car travels **9.2 miles less per gallon** than Grayson's car. **Answer:** Santiago’s car travels 9.2 miles less per gallon than Grayson’s car.