Analysis of Students' Abilities in Proportional Reasoning in Solving Mathematics Problems

Abstract

This research aims to analyze students' abilities in proportional reasoning in solving Mathematics problems on the Circle topic. The research type is a case study with the selection of subjects through purposive sampling. Data collection in this study was carried out with a mathematical pre-requisite ability test, a proportional reasoning ability test, and an interview. Two students from grade IX were selected based on their math pre-requisite ability test. Then, a proportional reasoning test was given to the subjects, and interviews related to the resulting test. The results of the research are as follows: (1) all subjects are able to show the indicators of additive thinking ability, (2) all subjects are able to show the indicators of multiplicative thinking ability, (3) subject two is able to show that indicator inability to use a reasonable or appropriate ratio while the subject one is not able to show that this indicator, (4) all subjects are not able to show that indicator inability to build a unified structure and (5) all subjects are not able to show that indicator inability to understand invariance.