Proactive interference of seventh grade students in solving problems of the greatest common divisor

Problem-solving is a critical element in learning mathematics. The way students solve problems can be identified using the Polya problem-solving process. Nonetheless, some students still experience barriers in solving problems of the Least Common Multiple and Greatest Common Divisor simultaneously. The Least Common Multiple and Greatest Common Divisor problems are distinct from one to another, but those have a similar solving procedure, i.g., determining prime factorization. Students were confused due to the similar steps in solving the Least Common Multiple and Greatest Common Divisor problems. This study aims to describe students’ thinking interference in solving the issue of the Greatest Common Divisor. This research was conducted by analyzing the work of seventh-grade students of Islamic Integrated Junior High School Al Fahmi Palu in solving Greatest Common Divisor problems. Furthermore, to obtain the supplementary data, an interview was conducted to a student who experiences proactive interference in solving the Greatest Common Divisor problem. The results of this study indicate that proactive interference occurred when students were solving the Greatest Common Divisor problem using the Least Common Multiple strategies. This study suggests that further researchers can examine other subjects with retroactive interference and conduct future studies on learning models to reduce the occurrence of proactive and retroactive interference.