Why is the world price 6? I understand the world price will be between 5 to 8, do not understand how to calculate exactly to get 6.

Attached file below is the explanation I have, and the question was on Ricardo model.

When country A, it takes a worker 3 hours to produce a bushel on Cotton and 24 hours to produce a computer, while country B it takes 2 hours to produce cotton and 10 hours to produce a computer. Country a has total 120 hours of labor, b has 200.

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