Math Quiz: NYT Learning Network

Through Math for America, I am part of an on-going collaboration with the New York Times Learning Network.  My latest contribution, a Test Yourself quiz-question, can be found here:

http://learning.blogs.nytimes.com/2011/02/2/test-yourself-math-feb-2-2011/

This problem involves estimating the per-person health care expenditures in the United States.