A consumer of a single commodity is in equilibrium when
His marginal utility is equal to zero
He can equate his demand with price
He equates marginal utility and price
He can equate his marginal and total utilities
Correct answer is C
A consumer is in equilibrium when the marginal utility equal to the price of the commodity i.e MUx = Px.
Where : X = the commodity
MU = Marginal utility
P = price of the commodity
Therefore, a consumer who consume a single commodity such as apple will be at equilibrium when MUa = Pa