40. While waiting in line to buy two tacos at 80 cents each and a medium drink for 90 cents, Jordan
notices that the restaurant has a value meal containing three tacos and a medium drink all for $3. For
Jordan, the marginal cost of the third taco would be:
41. While waiting in line to buy a cheeseburger for $2 and a drink for 75 cents, Aaron notices that the
restaurant has a value meal containing a cheeseburger, drink, and French fries for $3. For Aaron, the
marginal cost of purchasing the French fries:
cannot be determined because the information about the price of the French fries is not
provided.
42. While waiting in line to buy one cheeseburger for $1.50 and a medium drink for $1.00, Sally notices
that she could get a value meal that contains both the cheeseburger and medium drink and also a
medium order of fries for $2.75. She thinks to herself, “Is it worth the extra 25 cents to get the medium
fries?” To an economist, Sally’s decision is an example of:
basing decisions on total, rather than marginal, value.
an unintended consequence.
the fallacy of composition.
43. Just before class, Jim tells Stuart, “Stuart, you shouldn’t skip class today because you have paid tuition
to enroll in the class.” Stuart ignores Jim’s advice, and instead makes the decision of whether to attend
based on the importance to his grade that he feels he’d be missing that day in class relative to his value
of the extra time he could have to finish the video game he is playing. To an economist, Stuart is:
ignoring the total value of attending class.
ignoring the concept of opportunity cost.
44. Susan wishes to buy gasoline and have her car washed. She finds that if she buys 9 gallons of gasoline
at $1.50 per gallon, the car wash costs $1, but if she buys 10 gallons of gasoline, the car wash is free.
For Susan, the marginal cost of the tenth gallon of gasoline is: