Analysis of Students' Errors in Solving Word Problems on Sequences and Series in a Wetland Context, Based on Kastolan’s Error Theory

Abstract

Students frequently encounter difficulties solving word problems, particularly those that require contextual understanding, conceptual application, and procedural accuracy. This study aims to analyze the types of errors students make and identify the dominant errors in solving sequence and series word problems set within a wetland environmental context. A descriptive approach was employed within a mixed-methods explanatory design. Data were collected through written tests and structured interviews, and subsequently analyzed using Kastolan's error theory, encompassing conceptual, procedural, and technical errors. The research subjects comprised 29 Grade XI-4 students at State Senior High School 13, Banjarmasin. Quantitative analysis was conducted to calculate the percentages for each error type and to determine the interview subjects, while qualitative analysis was used to examine the underlying causes of student errors. The findings revealed that students committed all three error types, with conceptual errors accounting for 27.84%, procedural errors for 36.08%, and technical errors for 36.08%. Procedural and technical errors were identified as the dominant error types. Procedural errors were characterized by unsystematic solution steps and the omission of conclusions, whereas technical errors involved mistakes in arithmetic operations, mathematical notation, and value substitution. These dominant errors were primarily due to students' inability to interpret contextual information and translate it into appropriate mathematical models, as well as their lack of familiarity with systematically organizing solution steps. Interview data further confirmed that errors stemmed from insufficient understanding of mathematical modeling and computational inaccuracies. These findings underscore the importance of instructional approaches that prioritize conceptual understanding, procedural sequencing, and computational accuracy in solving contextual word problems.