Changes

For any given good or service, there is a supply and demand.  The supply can be described in terms of the possible production of different quantities at different prices.  The demand can be described separately as the willingness of the public to purchase different quantities at different prices.  The price is the key to both the supply and demand side; it is the price that determines the quantity transacted.

For any given good or service, there is a supply and demand.  The supply can be described in terms of the possible production of different quantities at different prices.  The demand can be described separately as the willingness of the public to purchase different quantities at different prices.  The price is the key to both the supply and demand side; it is the price that determines the quantity transacted.

No company can afford to build cars (supply them) if the sales price is only $1.  But at a sales price of $30,000, a vast number of cars can be built.  '''''The cause is price, and the effect is quantity.'''''

No company can afford to build cars (supply them) if the sales price is only $1.  But at a sales price of $30,000, a vast number of cars can be built.  '''The cause is price, and the effect is quantity''': the higher the market price for something, the more that manufacturers will want to make and sell it.

[[File:Red Lamborghini.png|200px|thumb|right|Impress the girls with this Lamborghini sports car, at a cost of $350,000.  Not much demand at that high price!]]

[[File:Red Lamborghini.png|200px|thumb|right|Impress the girls with this Lamborghini sports car, at a cost of $350,000.  Not much demand at that high price!]]

The demand for a good is also described in terms of price and quantity.  At a given price, there is a specific quantity demanded by the public for the good.  A billion people might buy a car if the price were only $1 (unrealistic).  At a much higher price of $30,000, the demand drops to a quantity of only millions sold (realistic).  At a still higher price of more than $100,000, the demand falls much further to the range of only a few thousand that can be sold (these are the very luxurious cars, like the Lamborghini sports car shown at the right).

The demand for a good is also described in terms of price and quantity.  At a given price, there is a specific quantity demanded by the public for the good.  A billion people might buy a car if the price were only $1 (unrealistic).  At a much higher price of $30,000, the demand drops to a quantity of only millions sold (realistic).  At a still higher price of more than $100,000, the demand falls much further to the range of only a few thousand that can be sold (these are the very luxurious cars, like the Lamborghini sports car shown at the right).