Three people carried goods with an average value of $20/kg. If a fourth person carried 10kg of goods worth $50/kg, and the average cost of all the goods carried was $30/kg, how much load was carried by the first three people?

Suppose that each country completely specializes in the production of the good in which it has a comparative advantage, producing only that good. in this case, the country that produces jeans will produce million pairs per week, and the country that produces corn will produce million bushels per week.