Tetty Natalia Sipayung, Ribka Kariani Sembiring
The purpose of this study is to find out the types of student errors that exisist in solving problem related to opportunities material. The subjects in this study were class IX students of the Junior High School of HKBP LubukPakam. The method of this study was descriptive with a qualitative approach through a case study. Based on the data analysis, the following results were obtained (1) No students experienced reading errors; (2) 25 students experience reading comprehension difficulties; (3) Seven students experienced transformation errors; (4) One student experienced a weakness in process skill; (5) Six students experienced encoding errors. The factors causing students errors consist of, students not understanding the explanation and purpose of the problem, students were confused which formula to use, students do not understand the procedure of problem solving, students were not careful in calculations or the process of problem solving. © 2019 Primrose Hall Publishing Group.
Dept. of Mathematics Education, Catholic University of Saint Thomas, Indonesia