Final answer:
Ethan's gas mileage can be represented by the equation y = 16 2x. To compare the rates of miles per gallon between Caiden and Ethan, you would need to know the specific value of x for each vehicle.
Step-by-step explanation:
Ethan's gas mileage can be represented by the same equation as Caiden's, which is y = 16 2x. The rate of miles per gallon for Ethan's vehicle will depend on the value of x, the number of gallons of gas. To compare the rates of miles per gallon between Caiden and Ethan, you would need to know the specific value of x for each vehicle.