For Method I and Method II (Kubaczka and Bandrowski, Chem. Engng Sci. 46, 539, 1991) of calculation of multicomponent mass transfer in mixtures of real fluids, the computation of "matrizant" in the form of a power function : [Phi] = [Phi(0)] + {[Phi(1)] - [Phi(0)]} x l(4) has been proposed. The results of the calculation of mass transport in the gaseous phase and in the process of multicomponent condensation in the presence of an inert component have been presented. Also a few variants of algorithms of calculation of fluxes for these methods with new and old forms of the "matrizant" function have been analyzed with the aim of selecting the most effective algorithm for a given method. It has been shown that the effectiveness of the chosen algorithm for Method I and Method II is comparable with the effectiveness of Taylor’s (Computers chem. Engng 6, 69-75 1982b) algorithm for the method of Stewart and Prober (Ind. Engng Chem. Fundam. 3, 224-235, 1964) and with that of the algorithm of Taylor and Webb (Computers chem. Engng 5, 61-73, 1981) for the method of Krishna (Chem. Engng Sci. 32, 659-667 1977).