PROPORTIONAL REASONING OF QUASI-ILLITERATE ADULTS

The main purpose of this paper is to describe the answers given by adults without primary schooling to different ratio- and rate-comparison tasks. The framework and the analysed data are part of an ongoing research, in which the responses of subjects of different ages and schoolings are studied. The behaviour of quasi-illiterate adults could throw some light on the effect of school on proportional reasoning in normal conditions; evidence will be shown regarding the similarities of their phenomenological behaviour with the one of people with regular schooling, especially the influence of number structure and context upon proportional reasoning. Part of an ongoing research on the strategies used by subjects of different ages and schoolings when faced to different kinds of ratio comparison tasks is reported in this paper. In the part here conveyed, we are concerned with the following question: Is proportional reasoning something developed exclusively at school, or does daily life provide the means to it? This question is difficult to answer in developed countries where all the population has a minimum of several years of schooling in which