The inelasticity of hadron-carbon nucleus collisions in the energy region exceeding 100 TeV is estimated from the carbon-emulsion chamber data at Pamirs to be K C = 0.65 ± 0.08. When combined with the recently presented data on hadronlead nucleus collisions taken at the same energy range it results in the K ∼ A 0.086 mass number dependence of inelasticity. The evaluated partial inelasticity for secondary (ν > 1) interactions, K ν>1 ≃ 0.2, suggests that the second and higher interactions of the excited hadron inside the nucleus proceed with only slight energy losses.