During the renaissance and the age of exploration (and beyond), countries tried to increase the amount of money in their treasuries. one way was to export more than it imported in order to create a favorable balance of trade. this theory is known as:

This theory is known as: mercatilism.

Explanation:

Mercantilism was a popular economic policy or system of trade that spanned and dominated Western European economic thought and policies from the sixteenth to the late eighteenth centuries before capitalism, used by the European countries in their imperialist ambitions and based on the idea that a nation's wealth and power were best served by soughting to increase exports more, restraining imports and increasing stores of gold and precious metals.

The term mercantilism, also called "commercialism,” was coined by Adam Smith.

The end of mercantilism was due to many causes. British mercantilism, closely linked with Britain's "old colonial system" (as distinct from the 19th century "new" colonial empire, which was to evolve eventually into the British Commonwealth of Nations), was brought to an end largely by the American Revolution.

answermarginal cost;