  We address a recent conjecture according to which the relaxation time $\tau$
of a viscous liquid obeys density scaling ($\tau=F(\rho^\gamma/T)$ where $\rho$
is density) if the liquid is ``strongly correlating,'' i.e., has almost 100%
correlation between equilibrium virial and potential-energy fluctuations
[Pedersen {\it et al.}, PRL {\bf 100}, 011201 (2008)]. Computer simulations of
two model liquids - an asymmetric dumbbell model and the Lewis-Wahnstr\"om OTP
model - confirm the conjecture and demonstrate that the scaling exponent
$\gamma$ can be accurately predicted from equilibrium fluctuations.
