Supposedly almost 80% of 200 economists surveyed at their annual meetings got this multiple choice question wrong:
"You won a free ticket to see an Eric Clapton concert (which has no resale value). Bob Dylan is performing on the same night and is your next-best alternative activity. Tickets to see Dylan cost $40. On any given day, you would be willing to pay up to $50 to see Dylan. Assume there are no other costs of seeing either performer. Based on this information, what is the opportunity cost of seeing Eric?"
Is the answer $0, $10, $40, or $50?
No googling this, people. Give me your thoughts in the comments.