Question

What happens to equilibrium price and quantity when there is a simultaneous increase in both demand and supply?

Hint:

Simultaneous shift rule:

• Same-direction shifts $\Rightarrow$ quantity certain
• Opposite price effects $\Rightarrow$ price uncertain
• Always compare relative magnitude of shifts

Answer 1

Step 1: Understanding equilibrium in a market.
Market equilibrium occurs at the point where quantity demanded by consumers becomes equal to the quantity supplied by producers. At this point, the equilibrium price and equilibrium quantity are determined in the market.

Step 2: Effect of an increase in demand.
When demand increases, the demand curve shifts to the right. This tends to increase both the equilibrium price and the equilibrium quantity because consumers are willing to buy more goods at each price level.

Step 3: Effect of an increase in supply.
When supply increases, the supply curve shifts to the right. This tends to decrease the equilibrium price and increase the equilibrium quantity because producers are willing to sell more goods at each price level.

Step 4: Simultaneous increase in demand and supply.
When both demand and supply increase at the same time, the equilibrium quantity will definitely increase because both forces increase the quantity traded in the market.
However, the effect on equilibrium price is uncertain. The price may increase, decrease, or remain unchanged depending on whether the increase in demand is greater than, less than, or equal to the increase in supply.

Final Answer:
When both demand and supply increase simultaneously, the equilibrium quantity increases for sure, while the equilibrium price may increase, decrease, or remain unchanged depending on the relative magnitude of the shifts in demand and supply.