Final answer:
The maximum amount a person is willing to pay for one additional unit of a good relates to the concept of consumer surplus and is influenced by the law of demand, which shows an inverse relationship between price and quantity demanded.
Step-by-step explanation:
The maximum amount that a person is willing to pay for one more unit of a good is fundamentally rooted in the concept of consumer surplus and the law of demand. Consumer surplus is the difference between the maximum price a consumer is willing to pay for a good and the actual market price of the good. The law of demand indicates an inverse relationship between price and quantity demanded, suggesting that as the price of a good increases, the quantity demanded decreases, and vice versa.
This economic principle assumes that all other factors affecting demand remain constant. For instance, if a new back pain drug is introduced at an equilibrium price of $600 per month with a quantity demanded of 20,000, but a government-imposed price ceiling reduces the price to $400, the quantity demanded might change, which can also alter the consumer surplus.