The planet Trantor has triple the mass of Earth, but only twice Earth’s radius. Compute the acceleration due to gravity at the surface of Trantor
g is proportional to M/R^2.
Tripling M while doubling R will multiply the Earth value of g by
3/(2^2) = 3/4.
Trantor's g value will be 9.81*(3/4) = 7.36 m/s^2