1. The problem statement, all variables and given/known data Determine the density of fictional planet in SI units from the information 2. Relevant equations Planets mass 1.28x10^22 Kg divided by radius 1.12x10^3Km = 1.14x10^25 Kg/m3 3. The attempt at a solution My answer seems all wrong, the SI unit should be in Kg/m cubed. Is radius equal to the volume as I feel that this is where the calculation went wrong, or maybe what I have got is right.