Mendoza , Tatiana, and David Block. “PERCENTAGE: AN ENCOUNTER BETWEEN RATIOS, FRACTIONS AND DECIMALS IN SCHOOL MATHEMATICS”. Revista Latinoamericana de Investigación en Matemática Educativa, vol. 13, no. 4(I), Mar. 2010, pp. 177-90, https://www.relime.org/index.php/relime/article/view/298.