What is the effect of a simultaneous increase in both supply and demand on equilibrium price and quantity?

Chapter 3 Outline
II. THE EFFECTS OF CHANGES IN DEMAND AND SUPPLY ON EQUILIBRIUM PRICE AND QUANTITY
A. Change in Demand
1. A change in demand will cause equilibrium price and output to change in thesame direction.
a. A decrease in demand will cause a reduction in the equilibrium price and quantity of a good.
1. The decrease in demand causes excess supply to develop at the initial price.
a. Excess supply will cause price to fall, and as price falls producers are willing to supply less of the good, thereby decreasing output.
b. An increase in demand will cause an increase in the equilibrium price and quantity of a good.
1. The increase in demand causes excess demand to develop at the initial price.
a. Excess demand will cause the price to rise, and as price rises producers are willing to sell more, thereby increasing output.
B. Change in Supply
1. A change in supply will cause equilibrium price and output to change inopposite directions.
a. An increase in supply will cause a reduction in the equilibrium price and an inase in the equilibrium quantity of a good.
1. The increase in supply creates an excess supply at the initial price.
a. Excess supply causes the price to fall and quantity demanded to increase.
b. An dcrease in supply will cause an increase in the equilibrium price and a decrease in the equilibrium quantity of a good.
1. The decrease in supply creates an excess demand at the initial price.
a. Excess demand causes the price to rise and quantity demanded to decrease.
C. Changes in Demand and Supply
1. If demand and supply change in opposite directions, then the change in theequilibrium price can be determined, but the change in the equilibrium. output cannot.
a. A decrease in demand and an increase in supply will cause a fall in equilibrium price, but the effect on equilibrium quantity cannot be determined.
1. For any quantity, consumers now place a lower value on the good, and producers are willing to accept a lower price; therefore, price will fall. The effect on output will depend on the relative size of the two changes.
b. An increase in demand and a decrease in supply will cause an increase in equilibrium price, but the effect on equilibrium quantity cannot be detennined.
1. For any quantity, consumers now place a higher value on the good,and producers must have a higher price in order to supply the good; therefore, price will increase. The effect on output will depend on the relative size of the two changes.
2. If demand and supply change in the same direction, the change in the equilibrium output can be determined, but the change in the equilibrium price cannot.
a. If both demand and supply increase, there will be an increase in the equilibrium output, but the effect on price cannot be determined.
1. If both demand and supply increase, consumers wish to buy more and firms wish to supply more so output will increase. However, since consumers place a higher value on each unit, but producers are willing to supply each unit at a lower price, the effect on price will depend on the relative size of the two changes.
b. If both demand and supply decrease, there will be a decrease in the equilibrium output, but the effect on price cannot be determined.
1. If both demand and supply decrease, consumers wish to buy less andfirms wish to supply less, so output will fall. However, since consumers place a lower value on each unit, but producers are willing to supply each unit only at higher prices, the effect on price will depend on the relative size of the two changes.

Demand and Supply models are very easy to use, when there is a change in either demand or supply. However, in reality, there are number of situations which lead to simultaneous changes in both demand and supply.

(I) Both Demand and Supply decrease

(II) Both Demand and Supply increase

(III) Demand decreases and Supply increases

(IV) Demand increases and Supply decreases

Let’s relate this to ridesharing businesses — Uber, Lyft, Ola — where the simultaneous shifts are seen in action. In the case of ridesharing businesses, the demand is the number of riders (Q) and the supply is the number of drivers (S).

(I) Both Demand and Supply Decrease:

Original Equilibrium is determined at point E, when the original demand curve DD and the original supply curve SS intersect each other. OQ is the equilibrium quantity and OP is the equilibrium price. The effect of decrease in both demand and supply on equilibrium price and equilibrium quantity can be better analyzed under three different cases:

Case 1: Decrease in Demand = Decrease in Supply:

What is the effect of a simultaneous increase in both supply and demand on equilibrium price and quantity?

When decrease in demand is proportionately equal to decrease in supply, then leftward shift in demand curve from D to D¹ is proportionately equal to leftward shift in supply curve from SS to S¹S¹ . The new equilibrium is determined at E¹ As demand and supply decrease in the same pro­portion, equilibrium price remains same at OP, but equilibrium quantity falls from OQ to OQ¹.

Impact: No change in Price for Riders. No change in Earnings for Drivers

Case 2: Decrease in Demand > Decrease in Supply:

What is the effect of a simultaneous increase in both supply and demand on equilibrium price and quantity?

When decrease in demand is proportionately more than decrease in supply, then leftward shift in demand curve from D to D¹ is proportionately more than leftward shift in supply curve from S to S¹. The new equilibrium is determined at E¹, equilibrium price falls from OP to OP¹ and equilibrium quantity falls from OQ to OQ¹.

Impact: Drop in Price for Riders. Drop Earnings for Drivers

Case 3: Decrease in Demand < Decrease in Supply:

What is the effect of a simultaneous increase in both supply and demand on equilibrium price and quantity?

When decrease in demand is proportionately less than decrease in supply, then leftward shift in demand curve from D to D¹ is proportionately less than leftward shift in supply curve from S to S¹. The new equilibrium is determined at E¹ equilibrium price rises from OP to OP¹ whereas, equilibrium quantity falls from OQ to OQ¹.

Impact: Increase in Price for Riders. Increase in Earnings for Drivers

(II) Both Demand and Supply Increase:

Original Equilibrium is determined at point E, when the original demand curve DD and the original supply curve SS intersect each other. OQ is the equilibrium quantity and OP is the equilibrium price. The effect of increase in both demand and supply on equilibrium price and equilibrium quantity is discussed under three different cases:

Case 1: Increase in Demand = Increase in Supply:

What is the effect of a simultaneous increase in both supply and demand on equilibrium price and quantity?

When increase in demand is proportionately equal to increase in supply, then rightward shift in demand curve from D to D1 is proportionately equal to rightward shift in supply curve from S to S¹. The new equilibrium is determined at E¹. As both demand and supply increase in the same proportion, equilibrium price remains the same at OP, but equilibrium quantity rises from OQ to OQ¹.

Impact: No change in Price for Riders. No change in Earnings for Drivers

Case 2: Increase in Demand > Increase in Supply:

What is the effect of a simultaneous increase in both supply and demand on equilibrium price and quantity?

When increase in demand is proportionately more than increase in supply then rightward shift in demand curve from D to D¹ is proportionately more than rightward shift in supply curve from SS to S1S1. The new equilibrium is determined at E1equilibrium price rises from OP to OP¹ and equilibrium quantity rises from OQ to OQ¹.

Impact: Increase in Price for Riders. Increase in Earnings for Drivers

Case 3: Increase in Demand < Increase in Supply:

What is the effect of a simultaneous increase in both supply and demand on equilibrium price and quantity?

When increase in demand is proportionately less than increase in supply, then rightward shift in demand curve from D to D¹ is proportionately less than rightward shift in supply curve from S to S¹. The new equilibrium is determined at E¹ equilibrium price falls from OP to OP¹ whereas, equilibrium quantity rises from OQ to OQ¹.

Impact: Decrease in Price for Riders. Decrease in Earnings for Drivers

(III) Demand decreases and Supply increases:

The effect of simultaneous decrease in demand and increase in supply on equilibrium price and equilibrium quantity is analyzed in the following three cases:

Case 1: Decrease in Demand = Increase in Supply:

What is the effect of a simultaneous increase in both supply and demand on equilibrium price and quantity?

Impact: Decrease in Price for Riders. Decrease in Earnings for Drivers

Case 2: Decrease in Demand > Increase in Supply:

Impact: Greater decrease in Price for Riders. Greater decrease in Earnings for Drivers

What is the effect of a simultaneous increase in both supply and demand on equilibrium price and quantity?

(IV) Demand increases and Supply decreases:

The effect of increase in demand and decrease in supply on equilibrium price and equilibrium quantity is discussed in the following three cases:

Case 1: Increase in demand = Decrease in supply:

What is the effect of a simultaneous increase in both supply and demand on equilibrium price and quantity?

Impact: Increase in Price for Riders. Increase in Earnings for Drivers

Case 2: Increase in Demand > Decrease in Supply:

What is the effect of a simultaneous increase in both supply and demand on equilibrium price and quantity?

Impact: Greater increase in Price for Riders. Greater increase in Earnings for Drivers

Case 3: Increase in Demand < Decrease in Supply:

What is the effect of a simultaneous increase in both supply and demand on equilibrium price and quantity?

Impact: Increase in Price for Riders. Increase in Earnings for Drivers

In this article, we just looked at the different possibilities of changes in supply and demand, and the impact on the pricing and earnings. In the next article, we look at levers such as surge pricing and incentives, which act as levers to adjust both supply and demand.

What are the impacts to price and quantity of a simultaneous increase in both supply and demand for a product?

An increase in supply, all other things unchanged, will cause the equilibrium price to fall; quantity demanded will increase. A decrease in supply will cause the equilibrium price to rise; quantity demanded will decrease.

What happens when demand and supply increase simultaneously?

When supply and demand both increase, the quantity of goods sold will also increase. If supply and demand both increase at about the same rate, the price of a product will remain steady. If demand increases more than supply, prices will rise.

What is the effect of changes in demand and supply on equilibrium price?

A decrease in demand will cause the equilibrium price to fall; quantity supplied will decrease. An increase in supply, all other things unchanged, will cause the equilibrium price to fall; quantity demanded will increase. A decrease in supply will cause the equilibrium price to rise; quantity demanded will decrease.

What is the effect on equilibrium price and quantity of an increase in both supply and demand quizlet?

If both supply and demand increase then both the equilibrium price and equilibrium quantity will always increase.