Automobiles get what percentage better mileage at 55 MPH compared to 70 MPH?

When considering fuel efficiency in automobiles, speed plays a significant role in determining mileage. Studies and various analyses indicate that vehicles tend to achieve optimal fuel economy at lower speeds, typically around 55 MPH. At this speed, vehicles experience less aerodynamic drag, which is a major factor affecting fuel consumption.

Research shows that traveling at 55 MPH can improve gas mileage by as much as 20% compared to traveling at 70 MPH. This reduction in fuel efficiency at higher speeds is largely due to the increased air resistance and drag that the vehicle faces as speed increases. Therefore, choosing to drive at 55 MPH not only helps to conserve fuel but also reduces emissions, making it a more environmentally friendly option.

Choosing 20% reflects a widely accepted figure in studies on vehicle efficiency, emphasizing the importance of speed on fuel consumption and making it the correct answer for this question.