Bahasa Indonesia

Mathematics arises because the human mind deals with ideas, processes and reasoning. The thought process carried out during science activities is a form of thinking called reasoning. In studying the concepts of Natural Sciences (IPA) requires two types of reasoning, namely deductive reasoning (deduction) and inductive reasoning (induction). Both types of reasoning help students think creatively, critically, analytically, meticulously and logically in dealing with everyday life problems. The purpose of this study is for students' ability to do mathematical reasoning, and examine the mastery of science concepts (Physics and Biology) in students of SMA Negeri Kodya Banda Aceh. The research method used is descriptive and correlational, to describe the ability of mathematical reasoning and mastery of science concepts (Physics and Biology). The subjects of the study population were all grade II students of SMA Negeri Kodya Banda Aceh. While the research sample subjects used were six classes from one of the Kodya State High Schools Banda Aceh which were determined purposively by the curriculum field. Research instrument to capture mathematical reasoning ability data using the Mathematical Reasoning Ability Test (TKPM). And mastery of the science concept using the Science Concept Mastery Test (TPKIPA) in the form of a description. As well as using the average value statistic ( ) and using the chi-squared formula (x2). The results of the study that mathematical reasoning skills in learning science concepts (Physics and Biology) on average are still in the category of lacking. The ability to reason mathematics has a high relationship with mastery of science concepts in high school students