The pilot might be correct (I think), because, if the gravity of the planet is strong, then the planet’s gravity will pull the spaceship into its orbit, so the engines don’t need to be on for the ship to get pushed toward the planet.
Let the first car's average speed be x
The second car's speed would be x+5
![2(x+(x+5))=210](https://tex.z-dn.net/?f=2%28x%2B%28x%2B5%29%29%3D210)
![2x+5=105](https://tex.z-dn.net/?f=2x%2B5%3D105)
![2x=100](https://tex.z-dn.net/?f=2x%3D100)
![x=50](https://tex.z-dn.net/?f=x%3D50)
So the speed of the slower car is 50mph, and the speed of the faster car is 55mph
Moment of force. Hope this helped