WASET
	%0 Journal Article
	%A Zhaohao Wang and  Lan Shu
	%D 2012
	%J International Journal of Mathematical and Computational Sciences
	%B World Academy of Science, Engineering and Technology
	%I Open Science Index 68, 2012
	%T The Lower and Upper Approximations in a Group
	%U https://publications.waset.org/pdf/9259
	%V 68
	%X In this paper, we generalize some propositions in [C.Z. Wang, D.G. Chen, A short note on some properties of rough groups, Comput. Math. Appl. 59(2010)431-436.] and we give some equivalent conditions for rough subgroups. The notion of minimal upper rough subgroups is introduced and a equivalent characterization is given, which implies the rough version of Lagranges Theorem.

	%P 1147 - 1151