The opportunity cost of a cup of coffee is 1/3 cups of cappuccinos.
The Production possibilities curve is a line that depicts the various combination of two goods a nation / individual / firm can produce when all its resources are fully utilised.
Opportunity cost of the next best option forgone when one alternative is chosen over other alternatives . As more coffees are produced less cappuccinos can be made.
The opportunity cost of a cup of coffee = (6 - 3) / (12 - 3) = 3/9 = 1/3.
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