Changes in Equilibrium Price and Quantity: The Four-Step Process


Table illustrates the market's demand and supply for cheddar cheese. Graph the data and find the equilibrium. Next, create a table showing the change in quantity demanded or quantity supplied, and a graph of the new equilibrium, in each of the following situations:

  1. The price of milk, a key input for cheese production, rises, so that the supply decreases by 80 pounds at every price.
  2. A new study says that eating cheese is good for your health, so that demand increases by 20% at every price.

Price per Pound Qd Qs
$3.00 750 540
$3.20 700 600
$3.40 650 650
$3.60 620 700
$3.80 600 720
$4.00 590 730

Table shows the supply and demand for movie tickets in a city. Graph demand and supply and identify the equilibrium. Then calculate in a table and graph the effect of the following two changes.

  1. Three new nightclubs open. They offer decent bands and have no cover charge, but make their money by selling food and drink. As a result, demand for movie tickets falls by six units at every price.
  2. The city eliminates a tax that it placed on all local entertainment businesses. The result is that the quantity supplied of movies at any given price increases by 10%.

Price per Pound Qd Qs
$5.00 26 16
$6.00 24 18
$7.00 22 20
$8.00 21 21
$9.00 20 22