The fraction of a floating object of volume V0 and density d0 above the surface of a liquid of density d will be
For the floatation V0d0g=Vindg⇒Vin=V0d0d
∴Vout=V0−Vin=V0−V0d0d=V0[d−d0d]
⇒VoutV0=d−d0d