Etnomatemática da Marimba: instrumento etnográfico da província de Malanje em Angola

Abstract

This article aims to identify mathematical relations associated with a musical instrument called Marimba;, it is a wooden artefact and with iron trestles, built in three villages in the province of Malanje, in Angola. We did an analysis of how to build this instrument in order to identify some mathematical relationships underlying the construction. We used the ethnographic method of data collection, through direct observation, semi-structured interviews with craftsmen, a photographic collection of Marimbas, videos related to their construction and, tuning and we studied this process in three villages of this Angolan’s province. The selected villages are - the village "Caiongo" and the village "Eucalyptus", both located, both, in the region of Calandula and the village “Mufuma” in the Kiwaba Nzoji region. These villages were selected because they are the communes (term used for the third-level administrative units in Angola after the municipalities) to build more Marimba in the Malanje province. The analysis of the elements - gourds and keys - used in its construction made it possible to identify some mathematical relationships related to their area and volume. The relationship between the areas and volumes found show differences between the sizes of these Marimba elements from one region to another. This type of study, using tools like this and others, can be introduced in the classroom to motivate students for learning mathematical concepts, showing its application to the reality that they are very close and that, no doubt, can contribute to the promotion of a cultural identity that should not be forgotten from generation to generation.