Abstract
In this paper, we have applied rough set theory to ordered Gamma-ideals mainly quasi(bi)-Gamma-ideals in ordered LA Gamma-semigroups by using pseudoorder of relations. Based on this relation we have studied properties of rough ideals, rough interior ideals, rough quasi-ideals, rough bi-ideals and rough prime ideals in ordered LA-Gamma-semigroups and have shown that lower and upper approximations of an LA-Gamma-subsemigroups (resp., left ideals, right ideals, interior ideals, two-sided ideals, quasi-ideals, bi-ideals and prime ideals) in an ordered LA-Gamma-semigroup is an LA-Gamma subsemigroups (resp., left ideals, right ideals, interior ideals, two-sided ideals, quasi-ideals, bi-ideals and prime ideals).