# How can I calculate the molar conductivity of a solution with multiple solutes?

I'm running an experiment mixing 2 different solutions, $\pu{5 mL}$ of $\pu{0.1 M}$ $\ce{NaCl}$ with $\pu{5 mL}$ of $\pu{0.1 M}$ $\ce{KCl}$. I am measuring the conductivity of the total solution in $\pu{mS/cm}$, and also measuring concentration of the electrolytes with electrolyte analyzer, so I will get the individual concentrations of $\ce{Na+, K+, Cl-}$ in the mixed solution.

How do I calculate this mixed solution total molar conductivity given these settings? The literature only shows the calculation for a single solution, and I couldn't find any reference on how to calculate this kind of combination.

If you are interested in the modelling of electrical conductivity of aqueous solutions containing more than a single salt, then there are already some references in literature, for example for the salinity of natural waters (Limnology and Oceanography Methods, doi 10.4319/lom.2008.6.489) or in systems relevant to chemical engineering (Ind. Eng. Chem. Res., doi 10.1021/ie9605903).

(from the latter)