Macroeconomics 1st Edition by Dean Karlan,Jonathan Morduch

Exercise 18

Two students are assigned to work together on a project that requires both writing and an oral presentation. Steve can write 1 page or prepare 3 minutes of a presentation each day. Anna can write 2 pages or prepare 1 minute of a presentation each day.
a. Who has a comparative advantage at writing?
b. Suppose that Steve goes to a writing tutor and learns some tricks that enable him to write 3 pages each day. Now who has a comparative advantage at writing?