Dear Student
MRT is the rate at which the units of one good have to be sacrificed to produce one more unit of the other good in a two goods economy. Suppose an economy produces only two goods X and Y. Further suppose that by employing these resources fully and efficiently, the economy produces 1X + 10Y. If the economy decides to produce 2X it has to cut down the production of Y by 2 units. Then 2Y is the opportunity cost of producing 1X. Then 2Y:1X is the MRT
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