Dina is training for a triathlon, a timed race that combines swimming, biking, a
ID: 1223122 • Letter: D
Question
Dina is training for a triathlon, a timed race that combines swimming, biking, and running.
Consider the following sentence: Because her pool sessions are helping her swim more quickly, Dina plans to reduce by 1 hour per week the time she spends training on the bike and increase by 1 hour the time she spends in the swimming pool; however, her husband says that she should stop doing any biking and running and spend all 20 hours per week in the pool. Which basic principle of individual choice does Dina's plan illustrate that her husband's advice does not?
A) Resources are scarce.
B) Many decisions are made on the margin.
C) All costs are opportunity costs.
D) People usually exploit opportunities to make themselves better off.
Explanation / Answer
B) Many decisions are made on the margin.'
The principle Many decisions are made on the margin state that many economics decisions are made by looking at the cost-benefit at the margin. This would involve looking at the cost-benefit of an additional unit of consumption or production. In the above case, Dina wants to spend an extra hour that would improve her swimming that would improve her chances at doing well in triathlon.