Authors:Sukiyanto Sukiyanto, Syamsulrizal Syamsulrizal, Dewi Anggreini First page: 153 Abstract: This study aimed to identify students' conceptual mental models in understanding the concept of prime factors. This study uses a qualitative and descriptive approach, using subjective analysis. Subjects in this study amounted to 71 students in class VII. The research instrument used is a test consisting of two questions. At the same time, the data collection techniques use interviews. Based on the results of data analysis, it was found that as many as subjects were included in the conceptual mental model. Furthermore, from the research results, it can be seen that students' conceptual mental models in understanding prime factors of a number, namely, students can use factor trees and understand prime numbers. This is supported by the results of interviews with three subjects stating that students can prove that 5 and 3 are prime factors of N while 15 and 45 are not prime factors of N; this is because 3 and 5 are prime numbers while 15 and 45 are not numbers. Primes In addition, students can prove that is the prime factorization of M. PubDate: 2021-11-27 DOI: 10.21274/jtm.2021.4.2.153-164 Issue No:Vol. 4, No. 2 (2021)

Authors:Fadhila Kartika Sari, Anies Fuady First page: 165 Abstract: Communication style is a way in which a person conveys messages or information. Pre-service teachers need to have good communication skills. Communication is one of the keys to the effectiveness of a learning process. Mathematical communication is divided into two, namely written communication and oral communication. Interactive learning videos are one of the alternative media used in online learning. This study aims to describe the mathematical communication style of pre-service teachers in conveying the material of Inequalities through interactive learning videos. This study uses a qualitative approach. The purposive sampling technique was chosen as the sampling method. The subjects of this study consisted of three students from the mathematics education study program FKIP UNISMA, each of which represented a different cohort level, namely semesters 2, 4, and 6. The results of the three subjects have a distinctive and different communication style in explaining the material of Absolute-Value Inequalities. Based on data analysis, the first student’s communication style tends to be non-assertive, the second student has a manipulative communication style, and the third student’s communication style tends to be more assertive. PubDate: 2021-11-27 DOI: 10.21274/jtm.2021.4.2.165-174 Issue No:Vol. 4, No. 2 (2021)

Authors:Fini Rezy Enabela Novilanti, Weni Dwi Susanti, Suripah Suripah First page: 175 Abstract: Currently, the learning process is still done online. This is a challenge for teachers to continue to apply problem-solving skills in the mathematics learning process. One of the appropriate mathematics materials to measure students' problem-solving abilities is geometry. Geometry material is often an obstacle for students because geometry material is abstract. Therefore, teachers must analyze students' problem-solving skills during the COVID-19 pandemic, especially geometry material. The purpose of this study was to describe students' problem-solving ability in answering geometry questions given by the teacher. This study uses descriptive qualitative research because of the Covid-19 pandemic. The subjects used were 20 students of grade VIII from one of the schools in Pekanbaru. The sampling technique used in this research is purposive sampling technique. The instruments used are test instruments, interviews, and documentation of student answers. Data analysis used was descriptive qualitative method referring to the Polya error indicator. The results of this study indicate that students' problem-solving abilities are still relatively low. This can be seen from some students experiencing difficulties solving the given geometry problems. So that teachers must be able to improve students' problem-solving abilities. PubDate: 2021-11-27 DOI: 10.21274/jtm.2021.4.2.175-186 Issue No:Vol. 4, No. 2 (2021)

Authors:Endri Puji Lestari, Shofan Fiangga First page: 187 Abstract: This study research to determine the differences in the types of errors and the cause students' errors in solving fraction story problems by male and female students in terms of Newman's theory. This research is using a qualitative approach to the type of case study. The subjects of this study were 3 male and 3 female students in grade VII MTsN 2 Trenggalek. The selection of research subjects was carried out based on the same mathematical ability and the suitability of gender criteria. The data collection techniques are written tests, unstructured interviews, and documentation. Data analysis techniques are data reduction, data presentation, and conclusion drawing. Based on the results of the study, (1) it was not found that male students and female students made reading errors, (2) male students and female students made comprehension errors with the same percentage, the cause was not writing down what was known and asked, (3) only male students made a transformation errors, the cause was choosing the wrong operation, formula, not converting the problem into mathematical form, (4) male students making process skill errors with a higher percentage than female, the cause was student perform the wrong operations, processes, and calculation results, while female students make mistakes in the process and calculation results, (5) male students make encoding error with higher percentage, the cause was students incorrectly or not writing the final answer. PubDate: 2021-11-27 DOI: 10.21274/jtm.2021.4.2.187-200 Issue No:Vol. 4, No. 2 (2021)

Authors:Risa Dewi Munika, Retno Marsitin, Nyamik Rahayu Sesanti First page: 201 Abstract: This development research aims to determine the process of developing E-LKPD (Electronic Student Worksheets) based on Problem Based Learning accompanied by interactive math quizzes to improve students' critical thinking skills that are valid, feasible and effective. The results of observations of mathematics learning in class X MIPA at SMAN 1 Malang show that there are no teaching materials that use interactive live worksheets. Critical thinking is the ability to solve problems which include steps to identify, organize and implement strategies and techniques, evaluate and draw conclusions. This type of research is the development of the ADDIE model (Analysis, Design, Development, Implementation, Evaluations). The research results from the validity test have an average of 3.33 by design experts with a very valid category, 3.27 by mathematics learning experts with a very valid category and 3.11 by material experts with a valid category. The results of the feasibility test on a small scale obtained a percentage of 81% with a very feasible category and 86% on a large scale trial with a very feasible category. The results of the effectiveness test obtained a percentage of completeness 100% in small-scale trials and 86% in large-scale trials so that both obtained effective categories. The conclusion of this study is that E-LKPD based on Problem Based Learning with interactive math quizzes is valid, feasible and effective and can improve students' critical thinking skills. PubDate: 2021-11-27 DOI: 10.21274/jtm.2021.4.2.201-214 Issue No:Vol. 4, No. 2 (2021)

Authors:Nuri Hidayati, Ahmad Anis Abdullah Pages: 215 - 224 Abstract: The ability to solve problems is a basic ability which is one of the goals of learning mathematics. Contextual Teaching and Learning (CTL) based on ethnomathematics can be a solution to improve students' mathematical problem solving abilities with a cultural approach around students. This study aims to determine the effectiveness of the application of ethnomathematical-based CTL model on the mathematical problem solving abilities of class VIII students of SMP N 1 Bambanglipuro. This research is a quantitative research with a quasi-experimental type. The design of this research is non-equivalent control group design. The population in this study were all eighth grade students of SMP N 1 Bambanglipuro for the 2020/2021 academic year. Purposive sampling technique used to select class VIII A as the control class, conducted 24 students, and class VIII C as the experimental class, conducted 24 students. The instrument used to determine the level of student problem solving is in the form of Prisma essay test material. The data analysis technique used is the average difference test using the t-test. The results showed that the average mathematical problem solving of students with the ethnomathematics-based CTL model was more than the average mathematical problem solving of students with conventional learning. Thus it can be said that the application of ethnomathematical-based CTL is effective in solving students' mathematical problems. PubDate: 2021-11-27 DOI: 10.21274/jtm.2021.4.2.215-224 Issue No:Vol. 4, No. 2 (2021)

Authors:Gusti Firda Khairunnisa, Frida Siswiyanti Pages: 225 - 234 Abstract: Giving assignments as an assessment in online learning during the pandemic needs to be well-considered properly so that students are not frustrated with the piling up tasks but are unable to give educators an idea of students' concepts understanding. This qualitative study aims to describe students’ responses to assignments in the form of journal writing in the Real Analysis course. The research was conducted by asking 109 students who took the Real Analysis class to write journal. At the end of the semester, students were asked to fill out a survei to find out the student's response to the task of writing a journal. Several students were then interviewed to get a more detailed information of the responses given in the survei. The results showed that 94% of the 109 students considered journal writing assignments need to be given in the Real Analysis course. As many as 99% of students agree that the feedback given by the lecturer helps students understand the material. Finally, 94% of students agree that journal-writing assignments are effective for improving understanding in the Real Analysis course. The results of the analysis of journals written by students showed that on average, more than 80% of students wrote notes related to concepts they had previously. It shows a meaningful learning process so that journal-writing assignments can be an alternative to achieve meaningful learning, especially in online learning during a pandemic. PubDate: 2021-11-27 DOI: 10.21274/jtm.2021.4.2.225-234 Issue No:Vol. 4, No. 2 (2021)

Authors:Dwi Oktaviana, Abdillah Abdillah Pages: 235 - 250 Abstract: Students abilities differ when given questions that require representing aspects to appear. This is because the ability of mathematical representation is influenced by the characteristics of the student way of thinking. The purpose of this study was to analyze the mathematical representation abilities of students in graph theory in terms of the characteristics of the way of thinking. This type of research uses qualitative research in the form of case studies. The research subjects were class B students in the sixth semester of IKIP PGRI Pontianak with one student taken for ways of thinking in Concrete Sequences (SK), Abstract Sequences (SA), Concrete Random (AK), and Abstract Random (AA) with selected using purposive sampling technique. The main instruments in this research is the researcher and the necessary supporting instruments include test questions on mathematical representation abilities, questionnaires on the characteristics of ways of thinking, and interview guidelines. To test the validity of the data used triangulation techniques. Data analysis was performed by data reduction, data presentation and conclusion. The results of the study showed that students with the SK and Sa way of thinking had fulfilled all the indicators of mathematical representation abilities, namely verbal, visual, and symbolic representations because their way of thinking was detailed and mastered the concept, while students with the AA and AK thinking only met the indicators of verbal representation due to the unstructured way of thinking and not mastering the concept. PubDate: 2021-11-27 DOI: 10.21274/jtm.2021.4.2.235-250 Issue No:Vol. 4, No. 2 (2021)