=+4. Two countries, Richland and Poorland, are described by the Solow growth model. They have the same Cobb–Douglas production function, F(K, L) = A KL1−, but with different quantities of capital and labor. Richland saves 32 percent of its income, while Poorland saves 10 percent.

Richland has population growth of 1 percent per year, while Poorland has population growth of