In a competitive market, the quantity and the price would be set simultaneously by the invisible hand.

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You see in your internal visualizer a chart of supply and demand, price and quantity, perhaps depicted as a large X on a graph with two axes.

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If you pick a quantity, then price and hence revenue are chosen by your customers.

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If you pick a price, then quantity, and hence revenue are chosen by your customers.

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In theory, a discretionary central bank could limit the quantity of money and achieve long-run price stability by controlling the growth of nominal final demand.

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Mr Powell works for EC Harris, one of the main firms of quantity surveyors who advise water companies on costs and estimates for price fixing negotiations.

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The whole idea of a cap-and-trade scheme is that you fix quantity, not price.

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And the price of most things tends to fall as quantity increases.

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His proposal also included a chained Consumer Price Index, which takes into account changes in quantity and prices of products, and an increase in the age of eligibility for Medicare, according to a source familiar with the talks.

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The increase in the demand for paper currency and gold not only had a quantity effect on the money supply but it also put upward pressure on the price of gold, which meant that dollar prices of all goods and services had to fall for the relative price of gold to rise.

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