Effects of instructional aids on integration of two or more asymmetric binary relations (e. g., A > B and B > C) were investigated as mentally handicapped students and non-handicapped first graders solved mathematical word problems. When inserted questions were given to those mentally handicapped students as they read mathematical word problems, critical effects of their processing resources on transitive inference were obtained. The results were interpreted in terms of facilitative effects of those instructional interventions on their understanding of both quantitative and ordinal relations among three elements of a set of objects.

Key words: mentally handicapped student, successive processing abilities, arithmetic word problem, number-line, inserted questions