Made available in DSpace on 2016-06-02T20:02:49Z (GMT). No. of bitstreams: 1 3865.pdf: 3136083 bytes, checksum: be5f23c6b90589dc90ec3ac89b46af5d (MD5) Previous issue date: 2011-09-01 / This paper has the aim to describe the design, development and application of guiding teaching activities in an area that is usually little explored, the Combinatorics. The study was developed through an intervention that consisted of three activities applied to guiding students in four classes of second grade high school of a state school in São Paulo. The activities were designed with the goal of putting students in a position of action and decision making to facilitate the understanding and the process of knowledge construction and were developed in groups of four or five students. The research classified as naturalist, by the fact that data collection was carried out directly on the site where the problem, is the central issue is to verify whether the teaching of Combinatorics, without the excessive use of formulas, through tutoring activities and use of multiplicative principle, can improve the teaching and understanding of that content. The results were obtained by analyzing the activities addressed by the students who were recorded, by observation, by notes taken by the researchers and also by the evaluation at the end of the research. It was found that the activities were essential for guiding a better performance of students who felt more secure and confident to carry out new activities. These activities represent the final product of this work and it is expected that constitute reference material for teachers who tirelessly seek for new methodologies. / O presente trabalho tem por objetivo descrever a elaboração, o desenvolvimento e a aplicação de atividades orientadoras de ensino numa área que usualmente é pouco explorada, a Análise Combinatória. A pesquisa foi desenvolvida através de uma intervenção que contou com três atividades orientadoras aplicadas a estudantes de quatro turmas da 2ª série do Ensino Médio de uma escola pública estadual no interior paulista. As atividades foram elaboradas com o objetivo de colocar os alunos numa posição de ação e tomadas de decisões para facilitar o entendimento e o processo de construção do conhecimento e foram desenvolvidas em grupos de quatro ou cinco alunos. A pesquisa que classificamos como naturalista, pelo fato de que a coleta de dados foi realizada diretamente no local em que o problema acontece, tem como questão central verificar se o ensino de Análise Combinatória, sem o uso abusivo de fórmulas, através de atividades orientadoras e da utilização do princípio multiplicativo, pode melhorar o ensino e a compreensão desse conteúdo. Os resultados foram obtidos através da análise das atividades resolvidas pelos estudantes que foram filmadas, pela observação e pelas anotações feitas pelos pesquisadores e também pela avaliação realizada ao final da pesquisa. Pôde-se constatar que as atividades orientadoras foram essenciais para um melhor desempenho dos estudantes que se sentiram mais seguros e confiantes para a realização de novas atividades. Essas atividades representam o produto final desse trabalho e espera-se que se constituam em material de consulta para professores que buscam, incansavelmente, novas metodologias.

A presente pesquisa investiga a aquisição do conceito de número racional na sua representação fracionária. O estudo justifica-se devido ao alto índice de dificuldades apresentadas pelos alunos na compreensão do conceito de número racional, que faz parte do pensamento multiplicativo. Apontamos a conexão entre os números fracionários e o raciocínio multiplicativo, destacando que as frações são números produzidos por divisões que resultam sempre em partes iguais. Nosso objetivo de pesquisa é comparar as estratégias cognitivas utilizadas por alunos com bom desempenho em Matemática com as estratégias cognitivas utilizadas por alunos que apresentam baixo desempenho escolar em Matemática, durante o processo de aquisição dos diferentes significados dos números fracionários: parte-todo, quociente e operador multiplicativo. Descrevemos as estratégias cognitivas utilizadas por cinqüenta alunos, de 4ª à 8ª séries do Ensino Fundamental, de uma escola privada da cidade de Porto Alegre. Verificamos a desconexão entre a compreensão dos alunos sobre a divisão e a aprendizagem de frações e a relacionamos à tendência metodológica de ensinar o conceito de número fracionário enfatizando somente o significado parte-todo. Constatamos que existem semelhanças na utilização das estratégias pelos alunos dos dois grupos. Percebemos que, embora as estratégias sejam comuns, os resultados mostram diferenças na recuperação automática de fatos na memória, que afetam a resolução de problemas mais complexos. A pesquisa aponta a necessidade de explorar a aquisição dos números fracionários em várias situações e em diferentes contextos, repensando o ensino de fração na escola. Tal ensino deve levar em consideração os conhecimentos informais, valorizar as diferentes estratégias utilizadas pelos alunos, promover interações entre eles para observar suas estratégias, proporcionar diversidade de ensino e reflexão das estratégias utilizadas, possibilitando um avanço no sentido de estratégias mais eficientes e econômicas. / The present research investigates the acquisition of the concept of rational number in its fractional representation. This study is justified due to the high degree of difficulty presented by students in understanding the concept of rational number, which is part of the multiplicative thought, observing that fractions are numbers produced by divisions which always result in equal parts. The objective of this research is to compare the cognitive strategies used by two groups of students: one with high performances in Math and the other one with low performance, during the process of learning different meanings of fractional numbers such as: whole-part, quotient’ and multiplicative operator. Cognitive strategies of fifty 4th to 8th Elementary School students from a private school in Porto Alegre were studied. A disconnection between the students’ understanding of division and their learning about fractions was verified. There is a tendency of teaching students the fractional number concept only emphasizing the meaning of the whole-part. Results of the research suggest that both groups of students used similar strategies and although strategies were alike, the results showed differences in the automatic retrieval of facts in the memory which affects solving higher complexity problems. The research shows the need of exploring the acquisition of fractional numbers in different situations and contexts, rethinking the teaching of fractions in schools. Such teaching should take into consideration informal knowledge, emphasize different strategies used by students, promote interaction between students in order to observe their strategies, and stimulate diversity in teaching and reflection on strategies used by students. Thus, more efficient and economical strategies would be possible.

This study examines how illustrations are used to introduce the concept of multiplication in Swedish mathematics textbooks intended for use with 2nd grade students. The aim is to find out how instructions and tasks are supported by illustrations by using a sociocultural perspective on learning with focus of mediating artifacts. The findings are compared to research in the field of mathematics didactics, where the importance of teaching multiplicative structures to primary school students is emphasized. With a method that categorize illustrations, insight is gained into how well they connect to the subject content, and in addition if they show additive or multiplicative multiplication. This study also looks into the extent that students are being instructed and encouraged to illustrate their answers to the textbook assignments. Results from the analyses of four 2nd grade mathematics textbook series, show that illustrations are used to a large extent to support text and numbers in introducing multiplication, but that all books contain pictures that contradict the subject content. The results also show that the majority of the illustrations demonstrate multiplication as repeated addition. Furthermore, this study suggests that when students are encouraged to draw pictures themselves, they are in most cases not given support and instructions to draw multiplicative multiplication. Based on earlier research within this field, as well as the findings of this study, it is argued that the dominant focus on repeated addition in illustrations can trap students in patterns of additive reasoning. This can interfere with their perception and comprehension of multiplication structure, and lead to limitations of students’ further development and understanding of mathematic concepts.

CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Esta pesquisa teve por objetivo analisar as contribuiÃÃes de metodologia desenvolvida, com suporte de tecnologias digitais, para o desenvolvimento do conceito de covariaÃÃo presente nas estruturas multiplicativas. Para isso, foram realizadas anÃlises das situaÃÃes presentes no campo conceitual multiplicativo, verificando a ocorrÃncia, ou nÃo, da covariaÃÃo. O desenvolvimento das atividades foi fundamentado em estudos relacionados Ãs contribuiÃÃes das mÃltiplas representaÃÃes para a aprendizagem e da abordagem seres-humanos-com-mÃdias. Utilizou-se, como metodologia, a pesquisa de intervenÃÃo. A investigaÃÃo foi realizada em uma Escola Municipal de Tempo Integral, localizada no municÃpio de Fortaleza - CearÃ, com estudantes de uma das turmas do 6 ano do Ensino Fundamental. A turma de alunos foi dividida em: Grupo Controle (GC), com 15 alunos e Grupo Experimental (GE), com 12 alunos. A investigaÃÃo foi dividida em trÃs etapas: prÃ-teste, intervenÃÃo e pÃs-teste. Todos os alunos, dos dois grupos, participaram do prÃ-teste e do pÃs-teste, aplicados individualmente e sem uso do computador. Tendo sido aplicados para diagnosticar os conhecimentos dos alunos em relaÃÃo à compreensÃo de situaÃÃes de proporÃÃo simples, de proporÃÃo mÃltipla, de proporÃÃo dupla, de interpretaÃÃo e construÃÃo de grÃficos lineares e compreensÃo de padrÃo de tabelas. A intervenÃÃo aconteceu apenas com o GE, no momento das aulas de MatemÃtica. Essa etapa teve duraÃÃo de 3 meses, com 18 encontros. As atividades desenvolvidas para esses encontros, utilizavam tecnologias digitais como: software Geogebra, recurso digital Equilibrando proporÃÃes, aplicativo online Cacoo, WhatsApp e blog. O GC manteve as aulas de MatemÃtica e de disciplinas eletivas, nos mesmos horÃrios do GE. Os dados foram analisados de modo a conhecer e compreender o desempenho dos alunos antes e apÃs as atividades; os teoremas-em-aÃÃo mobilizados durante a intervenÃÃo e suas evoluÃÃes; e as contribuiÃÃes das tecnologias usadas para a compreensÃo do conceito de covariaÃÃo. Os estudantes submetidos à intervenÃÃo apresentaram, estatisticamente, um desempenho superior, quando comparados aos estudantes do GC, demonstrando a eficÃcia da metodologia. Constatou-se, ainda, a modificaÃÃo de esquemas por meio de estratÃgias mais elaboradas, mesmo para situaÃÃes que jà eram conhecidas pelos estudantes do GE. As tecnologias digitais utilizadas contribuÃram para a compreensÃo da invariÃncia e da covariaÃÃo, ao relacionar mÃltiplas representaÃÃes de forma dinÃmica, possibilitar a produÃÃo de conhecimento e a significaÃÃo de contextos sociais e matemÃticos.

A presente pesquisa investiga a aquisição do conceito de número racional na sua representação fracionária. O estudo justifica-se devido ao alto índice de dificuldades apresentadas pelos alunos na compreensão do conceito de número racional, que faz parte do pensamento multiplicativo. Apontamos a conexão entre os números fracionários e o raciocínio multiplicativo, destacando que as frações são números produzidos por divisões que resultam sempre em partes iguais. Nosso objetivo de pesquisa é comparar as estratégias cognitivas utilizadas por alunos com bom desempenho em Matemática com as estratégias cognitivas utilizadas por alunos que apresentam baixo desempenho escolar em Matemática, durante o processo de aquisição dos diferentes significados dos números fracionários: parte-todo, quociente e operador multiplicativo. Descrevemos as estratégias cognitivas utilizadas por cinqüenta alunos, de 4ª à 8ª séries do Ensino Fundamental, de uma escola privada da cidade de Porto Alegre. Verificamos a desconexão entre a compreensão dos alunos sobre a divisão e a aprendizagem de frações e a relacionamos à tendência metodológica de ensinar o conceito de número fracionário enfatizando somente o significado parte-todo. Constatamos que existem semelhanças na utilização das estratégias pelos alunos dos dois grupos. Percebemos que, embora as estratégias sejam comuns, os resultados mostram diferenças na recuperação automática de fatos na memória, que afetam a resolução de problemas mais complexos. A pesquisa aponta a necessidade de explorar a aquisição dos números fracionários em várias situações e em diferentes contextos, repensando o ensino de fração na escola. Tal ensino deve levar em consideração os conhecimentos informais, valorizar as diferentes estratégias utilizadas pelos alunos, promover interações entre eles para observar suas estratégias, proporcionar diversidade de ensino e reflexão das estratégias utilizadas, possibilitando um avanço no sentido de estratégias mais eficientes e econômicas. / The present research investigates the acquisition of the concept of rational number in its fractional representation. This study is justified due to the high degree of difficulty presented by students in understanding the concept of rational number, which is part of the multiplicative thought, observing that fractions are numbers produced by divisions which always result in equal parts. The objective of this research is to compare the cognitive strategies used by two groups of students: one with high performances in Math and the other one with low performance, during the process of learning different meanings of fractional numbers such as: whole-part, quotient’ and multiplicative operator. Cognitive strategies of fifty 4th to 8th Elementary School students from a private school in Porto Alegre were studied. A disconnection between the students’ understanding of division and their learning about fractions was verified. There is a tendency of teaching students the fractional number concept only emphasizing the meaning of the whole-part. Results of the research suggest that both groups of students used similar strategies and although strategies were alike, the results showed differences in the automatic retrieval of facts in the memory which affects solving higher complexity problems. The research shows the need of exploring the acquisition of fractional numbers in different situations and contexts, rethinking the teaching of fractions in schools. Such teaching should take into consideration informal knowledge, emphasize different strategies used by students, promote interaction between students in order to observe their strategies, and stimulate diversity in teaching and reflection on strategies used by students. Thus, more efficient and economical strategies would be possible.

Submitted by Rafael Santana (rafael.silvasantana@ufpe.br) on 2017-08-03T18:54:38Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertação Anna Barbara Barros Leite Versão OFICIAL.pdf: 1917016 bytes, checksum: aca0b2a74aed357f595f412f83be6e75 (MD5) / Made available in DSpace on 2017-08-03T18:54:38Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertação Anna Barbara Barros Leite Versão OFICIAL.pdf: 1917016 bytes, checksum: aca0b2a74aed357f595f412f83be6e75 (MD5) Previous issue date: 2016-02-26 / CNPQ / Tomando por base as discussões da Teoria dos Campos Conceituais (Vergnaud, 1983, 1988, 2011) este estudo se propôs a descrever e classificar resoluções e estratégias desenvolvidas por estudantes dos anos finais do Ensino Fundamental II ao resolverem duas atividades (computacional e não-computacional) que envolviam situações-problema de proporção dupla e proporção múltipla em relações diretamente proporcionais. Para Gitirana, Magina, Spinillo e Campos (2014), estas situações envolvem relações proporcionais entre, no mínimo, três pares de grandezas e apresentam características especificas em suas configurações: (i) nas situações de proporção dupla os conjuntos de grandezas estabelecem relações independentes entre si e (ii) nas situações de proporção múltipla os conjuntos de grandezas apresentam relações proporcionais conjugadas entre si. Participaram do estudo 90 estudantes, de ambos os sexos, com idades entre 11 a 15 anos, matriculados entres os 7º, 8º e 9º anos do Ensino Fundamental II de uma escola pública da cidade do Recife, igualmente divididos em três grupos de 30 participantes por ano investigado. Os participantes realizaram duas atividades em momentos distintos: (i) atividade computacional, realizada coletivamente e envolvia resolução de quatro situações-problema alternadas entre proporção dupla e proporção múltipla; (ii) atividade não computacional, realizada individualmente, na qual os participantes apresentavam estimativas para resolver duas situações- problema (uma de proporção dupla e uma proporção múltipla). Os resultados encontrados foram analisados quanto ao número de acertos e as estratégias elaboradas para realização das duas atividades. Quanto ao desempenho, na atividade computacional, observou-se que a média geral foi alta para todos os anos (1,58 para proporção dupla e 1,73 para proporção múltipla) e não foi encontrada diferença significativa entre o desempenho nos dois tipos de situação em todos os anos escolares (p= 0,90). O desempenho encontrado na atividade não computacional apresentou médias mais baixas (0,70 para proporção dupla e 0,74 para proporção múltipla) e não apresentou diferença significativa nas médias entre os anos investigados (p= 0, 483). Ao comparar as médias gerais nas duas atividades, observou-se diferença significativa para situação de proporção múltipla (p= 0,04) apontando maior grau de dificuldade na atividade não-computacional, possivelmente relacionada a manipulação errada dos conjuntos de grandezas ou por incompreensão das relações proporcionais neste tipo de situação. Quanto às estratégias elaboradas, tanto na atividade computacional quanto na atividade não-computacional, os dados apontam o uso massivo do operador escalar entre as grandezas nas situações de proporção dupla, já nassituações de proporção múltipla, identificou-se elevado índice de estratégia mista, que se refere ao uso de relação escalar e funcional entre os conjuntos de grandezas. Os resultados permitiriam chegar à algumas conclusões: (i) situações computacionais de proporção dupla e múltipla apresentam o mesmo grau de dificuldade independente do grau de escolaridade; (ii) a compreensão das relações na situação de proporção múltipla, sem o registro escrito, apresentou-se como mais difícil para amostra e (iii) existem estratégias especificas para resolução de cada tipo de situação de acordo com suas configurações proporcionais. / Based on the discussions of the Theory of Conceptual Fields (Vergnaud, 1983, 1988, 2011) this study was to describe and classify resolutions and strategies developed by students of the final years of elementary school II to solve two activities (computational and noncomputational ) involving problem situations of double and multiple proportion ratio directly proportional relationships. To Gitirana, Magina, Spinillo and Campos (2014), these situations involve proportional relationships between at least three pairs of magnitudes and present specific features in their configurations: (i) in cases of double proportion the quantities of sets establish independent relations themselves and (ii) in situations of multiple proportions the quantities of conjugated sets have proportional relationships between them. The study included 90 students of both sexes, aged 11-15 years, enrolled entres the 7th, 8th and 9th grades of elementary school II of a public school in the city of Recife, equally divided into three groups of 30 participants per investigated year. Participants performed two activities at different times: (i) computer activity held collectively and involved four alternate resolution problem situations between double and multiple proportion ratio; (Ii) computer activity, carried out individually, in which participants presented estimates to solve two problem situations (a double ratio and a multiple ratio). The results were analyzed for the number of hits and the strategies developed to carry out the two activities. As for performance, the computational activity, it was observed that the overall average was high for all years (1.58 to 1.73 for double ratio and multiple proportion) and there was no significant difference between the performance of both types of situation in all school years (p = 0.90). The performance not found on computer activity showed lower average (0.70 to 0.74 for double ratio and multiple proportion) and no significant difference in mean between the investigated years (p = 0, 483). Comparing the overall averages in both activities, there was a significant difference for multiple ratio status (p = 0.04) indicating greater degree of difficulty in non-computational activity, possibly related to wrong manipulation of sets of quantities or misunderstanding of proportional relations in this type of situation. As to elaborate strategies, both in computational activity as the non-computational activity, the data point to the massive use of the operator climb between the quantities in situations of double proportion, as in situations of multiple proportion, we identified high mixed strategy index, As regards the use of scalar and functional relationship between sets of variables. The results allow to reach some conclusions: (i) computer cases of double and multiple proportion with the same degree of difficulty regardless of the level of education; (Ii) an understanding of the relationships in the multiple ratio situation without the written record, was presented as more difficult to sample and (iii) there are specific strategies for resolving each situation according to their proportional settings.

This thesis documents the evaluation of several transparency techniques in aspects of quality and performance. Depth sorted alpha blending and the order-independent transparency techniques additive blending, multiplicative blending, unsorted alpha blending and depth peeling are examined. The theoretical concepts of these techniques are explained.

The Multiplicative Schwarz Preconditioned Inexact Newton (MSPIN) algorithm is presented as a complement to Additive Schwarz Preconditioned Inexact Newton (ASPIN). At an algebraic level, ASPIN and MSPIN are variants of the same strategy to improve the convergence of systems with unbalanced nonlinearities; however, they have natural complementarity in practice. MSPIN is naturally based on partitioning of degrees of freedom in a nonlinear PDE system by field type rather than by subdomain, where a modest factor of concurrency can be sacrificed for physically motivated convergence robustness. ASPIN, originally introduced for decompositions into subdomains, is natural for high concurrency and reduction of global synchronization. The ASPIN framework, as an option for the outermost solver, successfully handles strong nonlinearities in computational fluid dynamics, but is barely explored for the highly nonlinear models of complex multiphase flow with capillarity, heterogeneity, and complex geometry. In this dissertation, the fully implicit ASPIN method is demonstrated for a finite volume discretization based on incompressible two-phase reservoir simulators in the presence of capillary forces and gravity. Numerical experiments show that the number of global nonlinear iterations is not only scalable with respect to the number of processors, but also significantly reduced compared with the standard inexact Newton method with a backtracking technique. Moreover, the ASPIN method, in contrast with the IMPES method, saves overall execution time because of the savings in timestep size. We consider the additive and multiplicative types of inexact Newton algorithms in the field-split context, and we augment the classical convergence theory of ASPIN for the multiplicative case. Moreover, we provide the convergence analysis of the MSPIN algorithm. Under suitable assumptions, it is shown that MSPIN is locally convergent, and desired superlinear or even quadratic convergence can be obtained when the forcing terms are picked suitably. Numerical experiments show that MSPIN can be significantly more robust than Newton methods based on global linearizations, and that MSPIN can be more robust than ASPIN, and maintain fast convergence even for challenging problems, such as high-Reynolds number Navier-Stokes equations.

An n × n matrix factorization of a polynomial f is a pair of n × n matrices (P, Q) such that PQ = f In, where In is the n × n identity matrix. In this dissertation, we study matrix factorizations of an arbitrary element in a given unital ring. This study is motivated on the one hand by the construction of the unit object in the bicategory LGK of Landau-Ginzburg models (of great utility in quantum physics) whose 1−cells are matrix factorizations of polynomials over a commutative ring K, and on the other hand by the existing tensor product of matrix factorizations b⊗. We observe that the pair of n × n matrices that appear in the matrix factorization of an element in a unital ring is not unique. Next, we propose a new operation on matrix factorizations denoted e⊗ which is such that if X is a matrix factorization of an element f in a unital ring (e.g. the power series ring K[[x1, ..., xr]] f) and Y is a matrix factorization of an element g in a unital ring (e.g. g ∈ K[[y1, ..., ys]]), then Xe⊗Y is a matrix factorization of f g in a certain unital ring (e.g. in case f ∈ K[[x1, ..., xr]] and g ∈ K[[y1, ..., ys]], then f g ∈ K[[x1, ..., xr , y1, ..., ys]]). e⊗ is called the multiplicative tensor product of X and Y. After proving that this product is bifunctorial, many of its properties are also stated and proved. Furthermore, if MF(1) denotes the category of matrix factorizations of the constant power series 1, we define the concept of one-step connected category and prove that there is a one-step connected subcategory of (MF(1),e⊗) which is semi-unital semi-monoidal. We also define the concept of right pseudo-monoidal category which generalizes the notion of monoidal category and we prove that (MF(1),e⊗) is an example of this concept. Furthermore, we define a summand-reducible polynomial to be one that can be written in the form f = t1 + · · · + ts + g11 · · · g1m1 + · · · + gl1 · · · glml under some specified conditions where each tk is a monomial and each gji is a sum of monomials. We then use b⊗ and e⊗ to improve the standard method for matrix factorization of polynomials on this class and we prove that if pji is the number of monomials in gji, then there is an improved version of the standard method for factoring f which produces factorizations of size 2 Qm1 i=1 p1i+···+ Qml i=1 pli−( Pm1 i=1 p1i+···+ Pml i=1 pli) times smaller than the size one would normally obtain with the standard method. Moreover, details are given to elucidate the intricate construction of the unit object of LGK. Thereafter, a proof of the naturality of the right and left unit maps of LGK with respect to 2−morphisms is presented. We also prove that there is no direct inverse for these (right and left) unit maps, thereby justifying the fact that their inverses are found only up to homotopy. Finally, some properties of matrix factorizations are exploited to state and prove a necessary condition to obtain a Morita context in LGK.

Ratio is one of the key mathematics concepts included in the South African Mathematics curriculum. It is applied in other topics of the Grade 7 curriculum, including geometry, functions and relationships, algebra, similarity and congruency. The aim of this qualitative research study was to explore the difficulties that learners experience in learning ratio. The primary research question for the study was: What is Grade 7 learners’ knowledge of ratio? This research question was answered through the following secondary research questions: How do learners solve problems involving ratio? What is learners’ conceptual knowledge of ratio? And what learning difficulties do learners experience when learning about ratio? The study was informed by Kilpatrick, Swafford and Findell’s (2001) five strands of mathematical proficiency; however, the focus was on conceptual and procedural knowledge of ratio. The interpretivist paradigm and the single exploratory case study design were used to gain insight into the learning of ratio. Data was collected from Grade 7 learners (23 of the 35 learners originally sampled) through a self-developed test that followed the prescripts of the Grade 7 Mathematics curriculum in South Africa and through semi-structured interviews. The test scripts were analysed using the Atlas.tiTM windows coding system and the results were used to construct questions for the semi-structured interviews. The interviews were used to corroborate data emerging from the test. The results of the study indicated that Grade 7 learners can do simple and routine manipulations of ratio as well as non-proportional ratio problems but struggle to solve problems that require multiplicative thinking and proportional reasoning skills. Although there could be other factors contributing to learners’ struggle to tackle proportional ratio problems requiring multiplication and proportional reasoning, a lack of conceptual knowledge seemed to contribute significantly. / Dissertation (MEd)--University of Pretoria, 2020. / Science, Mathematics and Technology Education / MEd / Unrestricted