[WelbyT]

Running into an issue trying to develop a formula that will give the density (in g/L) as a function of the concentration (mass %) of CaBr2 solution.

An assumption being made is that this is a solution at room temperature, so we have a density of water being 1000g/L.

As a hypothetical situation, assume an initial concentration of 52%.

[Borek]

You can definitely try to fit the tabulated data, other than that I am not aware of any bulletproof method of developing such formulas from the first principles.