Resumen

This work, adopting a Wittgensteinian perspective, aims to analyze the language games that involve mathematical concepts present in certain work activities, as well as the rules of use of such concepts, comparing them with the existing rules in School Mathematics. The studies analyzed used Ethnomathematics as a research method to understand the generation, organization and dissemination of mathematical knowledge in certain professions, in particular carpenters, fishermen, farmers and artisans. In considering the language games present in the mathematical practices existing in these professions, it is possible to show that in some games rules are presented that have strong family similarities to the games that make up the School Mathematics when they need a written mathematics, however, the expression of language games orally assume different meanings for terms present in both grammars. In addition, it presents examples of the use of mathematical knowledge without the formalism and rigor present in the language games of School Mathematics. It is a way of doing mathematics generated by another grammar that uses other rules, in this case estimation and rounding, a type of rationality distinct from that which constitutes School Mathematics, but which is effective in that form of use.