In the first chapter, I consider a capacity and price bounded profit maximization problem in which a firm determines prices of multiple substitutable products when the supply or capacity of the products is limited and the prices are bounded. This problem applies broadly to many pricing decision settings such as for hotel rooms, airline seats, fashion, or other seasonal retail products, as well as any product line with shared production capacity. In this paper, I characterize structural properties of the constrained profit maximization problems under the Multinomial Logit (MNL) model and the optimal pricing solutions, and present efficient solution approaches. In the second chapter, I consider a data-driven profit maximization problem in which a firm determines the prices of multiple substitutable products. This problem applies broadly to many pricing decision settings such as for hotel rooms, airline seats, fashion, or other seasonal retail products. A typical data-driven optimization problem takes a two-step approach of parameter estimation and optimization for decisions. However, this often returns a suboptimal solution as the estimation error due to the variability in data impacts the quality of the optimal solution. I present the relationship between estimation error and quality of the optimal solution and provide a possible way to reduce the impact of the error on the optimal pricing decision under the MNL model. In the last chapter, I consider a facility layout design problem of a semiconductor fabrication facility (FAB). In designing a facility layout, the traditional approach has been to minimize the flow-weighted distance of materials through the automated material handling system (AMHS). However, distance focused approach sometimes yields one major issue, traffic congestion, that there is a question if it is truly a good criterion to design a layout. In this study, I try to understand what makes such congestion by analyzing the system dynamics and propose another approach with a concept of ``balancing the flow" that focuses more on resolving the congestion. Finally, I compare the performance of the two methods through the simulation of semiconductor FAB layouts.