Okay, we also have learned about marginal product of labor. What is the marginal product of labor of the 3 rd worker? Randall Sure, the marginal product of labor is the change in total output - in your case, the change in the total number of car washes a day - divided by the change in the number of workers. So, what it the marginal product of labor of the 3rd worker? Ty Happy Economics Mentor Randall What is the marginal product of labor for the 6th worker