This document summarizes the relationship between marginal product and average product in production. It defines production, factors of production, and the production function. It then shows a table with varying amounts of labor and capital inputs and the corresponding total, average, and marginal products. The table demonstrates that average product increases when marginal product is greater than average product, decreases when marginal product is less than average product, and is at its maximum when marginal product equals average product. Finally, it presents a 3-stage model to further illustrate the relationship between marginal product and average product over varying levels of input.