The definitions are so important because they are different things. When I am saying quantity demand, I am saying the amount of units consumers in a market are willing to purchase at a given price. When I say demand, I am referencing the the quantities being demand at various price points. Quantity demanded will change when price changes. Demand changes when something happens that makes individual consumers in a market desire the good more or less, causing them to want higher or lower quantities of a good or service at every price.
Chapter 3 Curiosities
question
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