A simple method to investigate retailer's ordering policy for the EPQ (Economic Production Quantity) model under trade credit derived without calculus

Huang and Huang (2008) offered the algebraic approach to investigate the retailer's replenishment policy under trade credit on the economic production quantity (EPQ) model. In this paper, we propose an arithmetic-geometric mean inequality method to simplify the algebraic method of completing perfect square established by Huang and Huang to find the optimal solution under the annual total relevant cost minimized. The proposed method is easy to understand and simple to use.