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:

https://learning.blogs.nytimes.com/2011/12/14/test-yourself-math-dec-14-2011/

This problem is related to the record low yields of acorns this year in the Northeast United States.