General problem-solving skills are of central importance in school mathematics achievement. Word problems play an important role not just in mathematical education, but in general education as well. Meaningful learning and understanding are basic aspects of all kinds of learning and it is even more important in the case of learning mathematics. In order to efficiently enhance students' problem solving skills they should be assigned world problems which are new to them and to which they themselves have to find the steps to the solution, the algorithm. A number of researches, experiments and scientific papers in the didactics of mathematics prove that the role of visual representations in word problem solving is essential. Visual representation often helps in understanding a problem. Using visual representations leads to a better understanding and to improving special mathematical reasoning. The present paper presents an experiment involving university students who have been asked to solve a logical problem. There were three experimental groups. The aim was to find out whether problem solving is more efficient when using the traditional method (working on paper, with pencil) or when using a model.