This study employs a hermeneutic phenomenological approach to explore students'
epistemological obstacles in solving permutation and combination problems, with the goal of
supporting the development of more effective teaching materials. The research involved 24
12th-grade high school students (14 males and 10 females) and used qualitative methods. Data
were collected through five diagnostic essay questions and semi-structured interviews to
identify epistemological obstacles in combinatorics. Students’ written responses and interview
transcripts were analyzed and interpreted to uncover the underlying obstacles. The findings
revealed several epistemological obstacles: (1) students were unable to identify all possible
answers from a given problem; (2) students could not differentiate between problems requiring
the concept of permutation and those requiring the concept of combination; (3) students
struggled to solve problems that differed from the example problems provided; and (4)
challenges in formulating a complete solution when faced with multiple conditions, despite
being able to calculate partial results. These insights suggest that teachers and future researchers
should consider students' epistemological obstacles when designing instructional materials,
particularly for topics in combinatorics such as permutations and combinations. Developing
learning resources based on these findings may enhance conceptual understanding and
problem-solving skills among students.
Keywords: combination, epistemological obstacles, phenomenological hermeneutic, permutation, problem
solving