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Zoe’s grandparents are excited about finally paying off their mortgage because, as they
say, “Our cost of housing is now zero.” Zoe should explain to them the economic
concept of:
marginal analysis: if the additional cost of housing is zero, then their additional
benefit is also zero.
opportunity cost: by living in the house, they are giving up the opportunity to sell
the house, buy a smaller one, and pocket the difference.
efficiency: If their cost of housing is now zero, they should let Zoe move in without
charging her any rent. Zoe is better off, and her grandparents aren’t hurt.
equity: it is unfair that some people are still paying off their mortgage.
The university recently inherited a large mansion from a wealthy alumnus. The
university plans to use the mansion for faculty parties and to house distinguished guests.
The opportunity cost of the mansion to the university is:
zero because it was a gift.
the original cost of building the mansion.
the amount the university would receive if it sold the mansion.
the cost of catering the parties at the mansion.
A new startup airline is offering a free round-trip ticket to Hawaii to the first 600 people
who enter the airline’s main office on the airline’s first day of business. You arrive 24
hours before it is scheduled to open to be sure to get the free ticket, and you buy food
from vendors while waiting in line. You successfully obtain the ticket. What was the
cost to you for obtaining the ticket?
the cost of food while you wait in line
the cost of food while you wait in line and the opportunity cost of your time spent
in line
the actual value of the ticket
A friend comes up to you and offers you a free ticket to a professional baseball game
that night. You decide to attend the game. The game takes five hours and costs you $15
for transportation. If you had not attended the game, you would have worked at your
part-time job for $8 an hour. What is the cost to you of attending the game?
The cost is zero—the ticket is free.