Demand and Supply

Read this chapter and attempt the "Try It" exercises. Also, complete the concept problems and the numerical problems at the end of the chapter. This chapter will help you gain familiarity and competencies with regard to basic demand and supply concepts. At a minimum, you should be able to list the factors that shift the demand curve and those that shift the supply curve. Make sure to carefully study the difference between demand and quantity demanded (and the difference between supply and quantity supplied).

3.3 Demand, Supply, and Equilibrium

ANSWER TO TRY IT! PROBLEM

An increase in the price of movie theater tickets (a substitute for DVD rentals) will cause the demand curve for DVD rentals to shift to the right. An increase in the wages paid to DVD rental store clerks (an increase in the cost of a factor of production) shifts the supply curve to the left. Each event taken separately causes equilibrium price to rise. Whether equilibrium quantity will be higher or lower depends on which curve shifted more.

If the demand curve shifted more, then the equilibrium quantity of DVD rentals will rise [Panel (a)].

If the supply curve shifted more, then the equilibrium quantity of DVD rentals will fall [Panel (b)].

If the curves shifted by the same amount, then the equilibrium quantity of DVD rentals would not change [Panel (c)].