The aim of this study is to determinate the difficulties that students of fourth course in secondary school, high school and teacher´s master of secondary school students have with operation and order when they realize calculations with periodic decimal numbers. The study is based in a previous article of Rittaud and Vivier which is a replica of a part of their test we used for data collection. The analysis of students’ answers allows identifying mistakes and deficiencies in education, leading to a classification scheme and interpretation of student performances.... [Leer más...]