Abstract: I have written this paper to my confidence that decision support systems and technologies can help traders and business owners in develop their business especially in making decisions related with investments. The paper give readers overview on techniques used in business and especially those they work in medium institution and those they interested in investment decisions. The results of research illustrate the best techniques can use in investments decisions and the best ways to use every technique. The scope of the work was in one of medium size enterprise, i use their data for the year of 2016 and make the study on this data. In this research, I argue that the use of scientific methods is better than relying on traditional methods such as the experience of people and others. In particular, I believe that the use of linear programming method is the best way to make investment decisions. The experiments in the research on two methods assuming stability of sold quantities in 2017 as 2016 and the second method by forecast o sold quantities in 2017 after studying time series of every item. The techniques that we use are traditional method as experience of persons our case study use it, data calculations but not rely on scientific method, linear programming and ABC XYZ analyse. The way the experiments were conducted was to focus on the highest return on profitability, taking into account the available financial resources of the institution as well as the expected period of return of profits.
Keywords: Decision support system, linear programming, medium sized enterprise, investment decisions