1. The problem statement, all variables and given/known data A proton, which is the nucleus of a hydrogen atom, can be modeled as a sphere with a diameter of 2.4 fm and a mass of 1.67e-27 kg. Determine the density of the proton. 2. Relevant equations As far as I know, the only required formula is D = m/v 3. The attempt at a solution Well my attempt looks like this: (2.4)^3*pi*(4/3) = 57.90583579 fm^3 Used google to convert that into kilometers, and got 57.905835791 (femtometer^3) = 5.79058358e-44 meter^3. Divided 1.67e-27 kg by 5.79058358e-44 meter^3. Got 2.883992566e16 but apparently, it's wrong. Any suggestions guys?