A Comparison of the Proportional Reasoning Abilities of Learning Disabled and Non-Learning Disabled Children and Adolescents
Noelting's (1980a, 1980b) three parallel instruments on proportional reasoning—two presenting problem-solving tasks in the ratio and division interpretations of fractions and one presenting the tasks in the purely symbolic form of numerical fractions—were administered to 6 female and 41 male learning disabled students, grades four through eight. Performances on the instruments were then compared to the performances of 120 non-learning disabled students in grades five through nine of the same school district. The purpose of the study was to determine whether learning disabled students differed in their development of proportional reasoning and whether their disability was in the use of symbols and language and not in their ability to solve proportional problems. Developmental scalograms, PPR>0.93, resulted in support of the hypothesis that the proportional reasoning abilities of the learning disabled student are developmental and thus not unlike those of the non-learning disabled student. A comparison of the three means for the two groups revealed a reversal in performance with the learning disabled students more successful at problem solving and the non-learning disabled students more successful at the purely symbolic form of numerical fractions. Unlike the non-learning disabled students, the learning disabled students' inability to express a strategy did not indicate an inability to solve the problem.