Suppose the demand and supply curve of commodity X in a perfectly competitive market are given by:
qD = 700 − p
qS = 500 + 3p for p ≥ 15
= 0 for 0 ≤ p <15
Assume that the market consists of identical firms. Identify the reason behind the market supply of commodity X being zero at any price less than Rs 15. What will be the equilibrium price for this commodity? At equilibrium, what quantity of X will be produced?
It is given that;
qd = 700 − p
qs = 500 + 3p for p > Rs 15
= 0 for 0 ≤ p < 15
The market supply is zero for any price from Rs 0 to Rs 15, this is because, for price between 0 to 15, no individual firm will produce any positive level of output (as the price is less than the minimum of AVC). Consequently, the market supply curve will be zero.
At equilibrium qd = qs
700 − p = 500 + 3p
− p −3p = 500 − 700
− 4p = − 200
p = 50
Equilibrium price is Rs 50.
Quantity = qs = 500 + 3p
= 500 + 3 (50)
= 500 + 150
= 650
Therefore, the equilibrium quantity is 650 units.