Students' Mathematical Understanding Ability In Pie Chart Material At Seventh Grade

This study aims to analyze the mathematical understanding ability of seventh-grade students on pie chart material, describe the ability profile per indicator, and identify dominant student error patterns. Mathematical understanding is a fundamental competency encompassing students' ability to comprehend concepts, apply procedures, and use mathematical representations appropriately. Pie charts, as part of statistics learning, require an integrative understanding of percentages, angles, and visual data representation. This study employed a descriptive quantitative approach involving 18 seventh-grade students at SMP Negeri 5 Sa'dan selected via purposive sampling. The instrument was a mathematical understanding test consisting of four essay items measuring six main indicators. Results indicate that students' overall mathematical understanding falls into the moderate category, with a mean score of 58.7 (scale 0–100) and mean scores ranging from 2.50 to 2.83 across indicators (scale 0–4). The lowest indicator was classifying objects ($2.50$), while applying concepts in problem-solving yielded the highest score ($2.83$). The dominant errors were procedural ($40%$), conceptual ($35%$), and interpretive ($25%$). These findings suggest that instruction should emphasize conceptual understanding of prerequisite concepts—particularly percentages and angle conversion—prior to procedural execution.