GPS: Distributive Property throughout the Grades

Growing Problem Solvers provides four original, related, classroom-ready mathematical tasks, one for each grade band. Together, these tasks illustrate the trajectory of learners’ growth as problem solvers across their years of school mathematics.

Necessary and Sufficient Conditions for The Solutions of Linear Equation System

A Semiring is an algebraic structure (S,+,x) such that (S,+) is a commutative Semigroup with identity element 0, (S,x) is a Semigroup with identity element 1, distributive property of multiplication over addition, and multiplication by 0 as an absorbent element in S. A linear equations system over a Semiring S is a pair (A,b) where A is a matrix with entries in S and b is a vector over S. This paper will be described as necessary or sufficient conditions of the solution of linear equations system over Semiring S viewed by matrix X that satisfies AXA=A, with A in S. For a matrix X that satisfies AXA=A, a linear equations system Ax=b has solution x=Xb+(I-XA)h with arbitrary h in S if and only if AXb=b.

Distributivity, partitioning, and the multiplication algorithm

Multiplicative thinking underpins much of the mathematics learned beyond the middle primary years. As such, it needs to be understood conceptually to highlight the connections between its many aspects. This paper focuses on one such connection; that is how the array, place value partitioning and the distributive property of multiplication are related. It is important that students understand how the property informs the written multiplication algorithm. Another component of successful use of the standard multiplication algorithm is extended number facts and the paper also explores students’ ability to understand and generate them. One purpose of the study was to investigate the extent to which students used the standard multiplication algorithm and if their use of it is supported by an understanding of the underpinning components of the array, partitioning, the distributive property, and extended number facts. That is, we seek to learn if students have a conceptual understanding of the multiplication algorithm and its underpinning mathematics that would enable them to transfer their knowledge to a range of contexts, or if they have procedurally learned mathematics. In this qualitative study, data were generated from the administration of a Multiplicative Thinking Quiz with a sample of 36 primary aged students. Data were analyzed manually and reported using descriptive statistics. The main implications of the study are that the connections among the multiplicative array, place value partitioning, base ten property of place value, distributive property of multiplication, and extended number facts need to be made explicit for children in terms of how they inform the use of the written algorithm for multiplication.

Kemampuan Pembuktian Matematis Mahasiswa Menggunakan Induksi Matematika

Kemampuan mahasiswa dalam melakukan pembuktian matematis tidak sama bergantung dari kategori kognitifnya. Salah satu metode pembuktian matematika adalah induksi matematika yang memerlukan pemahaman konsep secara sistematis. Tujuan penelitian adalah untuk mengetahui kemampuan pembuktian matematis mahasiswa yang memiliki kategori kognitif tinggi dan rendah menggunakan induksi matematika. Subjek penelitian ini adalah empat orang mahasiswa tingkat tiga Program Studi Pendidikan Matematika dengan klasifikasi dua orang mahasiswa memiliki kemampuan kognitif tinggi dan dua mahasiswa berkemampuan rendah. Instrumen penelitian yang digunakan adalah lembar tes materi induksi matematika dan pedoman wawancara. Penelitian ini merupakan penelitian deskriptif yang mendeskripsikan kemampuan pembuktian matematis mahasiswa dalam menyelesaikan soal terkait induksi matematika disesuaikan dengan kemampuan kognitif tinggi dan rendah. Hasil penelitian menunjukkan bahwa mahasiswa dengan kategori kognitif tinggi mampu menyelesaikan setiap langkah pembuktian secara benar namun belum sistematis, sedangkan yang berkemampuan kognitif rendah tidak memahami alur pembuktian pada langkah induksi, kekeliruan memahami sifat distributif, dan ketidakteraturan menghubungkan setiap langkah pembuktian. Melalui artikel ini, peneliti berharap dapat menganalisis perlakuan yang tepat pada mahasiswa saat mengajar berbagai materi matematika yang menggunakan prasyarat induksi matematika. Kata kunci: pembuktian matematis, induksi matematika, kemampuan kognitif. ABSTRACT The students’ ability to perform mathematical proof is different depending on their cognitive category. One of mathematical proofing is mathematical induction which requires concepts understanding systematically. The purpose of this research is to know the ability of mathematical proof using mathematical induction of high and low cognitive category students. The subjects of this study are four third graders of Mathematics Education Study Program. Two students have high cognitive ability and the others have low cognitive ability. The mathematical induction material test sheet and interview guideline are used as research instruments. This is a descriptive research which describes the mathematical proof ability of students in solving problems related to mathematical induction adjusted with high and low cognitive ability. The results show that students with high cognitive category are able to complete each step of proof correctly but not systematically. At the same time, the students with low cognitive ability are not understand the proof steps at the induction step, the misunderstood the distributive property, and the irregularity connect the proof steps. The researcher expects to analyze the appropriate treatment to the students while teaching mathematical materials using mathematical induction prerequisites. Keywords: mathematical proof, mathematical induction, cognitive ability.

Exploring Multiplication: Three-in-a-Row Lucky Numbers

This game-based activity prompts students to explore the structure of multiplication, experiment with the distributive property, and begin investigating prime numbers.

A REVIEW AND CONTENT ANALYSIS OF MATHEMATICS TEXTBOOKS IN EDUCATIONAL RESEARCH

Research collected and reviewed a number of empirical studies in the field of educational research regarding the analysis of mathematics textbooks to provide summary and overview the information there in. The questions were identified via Google Scholar and collected from different data sources. A total of 44 papers published from 1953 to 2015 were selected based specific criteria, with 24 articles include in the SSCI database. Descriptive statistics were used to evaluate and interpret the results. A perspective on the learning analysis methods was used to collect studies and showed the mathematics textbooks analyzed were investigated under four themes: The analysis of standards, distributive property, language in mathematics, and others. School’s level which is investigated textbooks: Kindergarten, elementary, junior school, and senior school. Subjects covered in the mathematics textbooks included algebra and arithmetic, geometry, measurement, data analysis and probability, number and operations, among others. Research found the most frequently discussed in perspective on learning was the analysis of the standards and the distributive property (15 studies), the most common subject was number and operations (16 studies), and the highest number in school’s level was elementary school (18 studies). Nevertheless, fewer studies have been found to analyzing mathematics textbooks. Future research can pay attention for the relevant theoretical issues and collaborate studies in more perspective learning analysis. Keywords: comparation of study, content analysis, mathematics textbooks.

Solving Hardy-Weinberg with Geometry: An Integration of Biology and Math

Introducing Hardy-Weinberg equilibrium into the high school or college classroom can be difficult because many students struggle with the mathematical formalism of the Hardy-Weinberg equations. Despite the potential difficulties, incorporating Hardy-Weinberg into the curriculum can provide students with the opportunity to investigate a scientific theory using data and integrate across the disciplines of biology and mathematics. We present a geometric way to interpret and visualize Hardy-Weinberg equilibrium, allowing students to focus on the core ideas without algebraic baggage. We also introduce interactive applets that draw on the distributive property of mathematics to allow students to experiment in real time. With the applets, students can observe the effects of changing allele frequencies on genotype frequencies in a population at Hardy-Weinberg equilibrium. Anecdotally, we found use of the geometric interpretation led to deeper student understanding of the concepts and improved the students' ability to solve Hardy-Weinberg-related problems. Students can use the ideas and tools provided here to draw connections between the biology and mathematics, as well as between algebra and geometry.