The degree of generality of inflation in FRW models with massive scalar field and hydrodynamical matter

Friedmann-Robertson-Walker cosmological models with a massive scalar field are studied in the presence of hydrodynamical matter in the form of a perfect fluid. The ratio of the number of solutions without inflation to the total number of solutions is evaluated, depending on the fluid density. It is shown that in a closed model this ratio can reach 60%, by contrast to $\sim 30 %$ in models without fluid.