MAITRA, S N. Four Problems on Ratio and Proportion With Their Solutions. SCHOOL SCIENCE, [S. l.], v. 59, n. 3-4, p. p. 40–42, 2021. Disponível em: http://ejournals.ncert.gov.in/index.php/SS/article/view/3869. Acesso em: 17 jun. 2025.