Assuming that the hydrogen atom is spherical;
Density Dh=m/v
Volume Vh= m/Dh but v=Vh.
Therefore, mass m of hydrogen atom is given by;
m= Dh*Vh =(m/Vh) *(m/Dh)
For proton;
Density Dp= m/v
Volume Vp= m/DP but v=Vp.
Therefore, mass m of hydrogen proton is given by;
m=Dp*Vp =(m/VP) *(m/DP)
Hence; DhVh=DpVp