Several studies related to mathematics understanding found that many undergraduate students lack some basic knowledge of algebra. They memorized only a few topics, formulas, and algorithms without understanding them conceptually, even though they could manipulate those limited number of points correctly or incorrectly. In comparison, most high-achieving students have incomplete solutions in Modeling Mathematics PISA-like tasks in levels 5 and 6, related to the content of change and relationship. In contrast, students with moderate achievement can solve the problem using instinct, trial and error, and logic. Therefore, this study aims to analyze students' algebraic conceptual understanding related to their modeling competence in solving a mathematical problem that is an adapted PISA task, using qualitative research as an appropriate method. It emphasizes a holistic description of the phenomena studied concerning how students work with algebraic conceptual problems and Mathematics task-like PISA problems. This study involved 244 new vocational college students in 5 study programs. Data collection used in this research is students' worksheets, video recording, and interviewing some students to obtain more profound information about their thinking processes. Furthermore, the data was analyzed by holistic description. Interpretation and conclusion using the definition of equation and algebra expression and indicator of modeling competence, mathematical literacy refers to the proficiency level of PISA question given as a guideline to interpret and make a conclusion. Some discovered strategies for solving the problem and implications regarding their mathematical literacy skills related to these tasks are discussed.