To find the radius of Mars, we can subtract the given difference from the radius of Earth.
Given:
Radius of Earth = 6,378.1 km
Difference between the radii = 2,981.1 km
To find the radius of Mars:
Radius of Mars = Radius of Earth - Difference between the radii
Radius of Mars = 6,378.1 km - 2,981.1 km
Radius of Mars = 3,397 km
Therefore, the radius of Mars is approximately 3,397 km.