ETHNOMATHEMATICS IN BUYING AND SELLING TRANSACTIONS CONTUCTED BY MANDAILING COMMUNITY OF MEDAN CITY

Abstract

This research proves that there is a connection between mathematics and culture and also knows that there are other ways to calculate arithmetic and its operations that are different from the way they are taught in school. This research is also expected to be useful to change people's opinion that math has no influence at all with culture. This research is a descriptive research with a qualitative approach. The data collection methods used were observation and interview. The research subjects were 5 sellers. The data analyzed in this study is the process of buying and selling transactions carried out by the Mandailing community of Medan City and how to calculate addition, subtraction, multiplication and division carried out by sellers and buyers. The results showed that the buying and selling process carried out by the community uses several methods, namely how they determine the selling price, how to calculate the addition, how the payment is made by the buyer, how the seller gives change to the buyer, how the seller gives the rest of the payment if the seller does not have change and how to round. The culture and language used around traditional markets is non-standard Indonesian or everyday language. However, when sellers and buyers who have the same ethnicity such as Mandailing will use Mandailing language in their interactions. Likewise, the interaction between sellers and other sellers.