Escape velocity?

Question

The escape velocity of a bullet from the surface of planet Y is 1759.0 m/s. Calculate the escape velocity from the surface of the planet X if the mass of planet X is 1.53 times that of Y, and its radius is 0.807 times the radius of Y.

Answer 1

It is proportional to the square root of mass over radius. So 1.53/.807 = 1.8959 and the square root of that is 1.3769. So the new escape velocity is 2422.0 m/s.