Essentials of Economics

Krugman, Paul; Wells, Robin

4th ed.

New York: Worth Publishers, Macmillan Learning, 2017

p. 254

Volume discounts. Often the price is lower if you buy a large quantity. For a consumer who plans to consume a lot of a good, the cost of the last unitxguiollargxthe marginal cost to the consumerxguiollargxis considerably less than the average price. This separates those who plan to buy a lot, and so are likely to be more sensitive to price, from those who don't.

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