MathDB
Students knowing English, German and French.

Source:

February 12, 2011
percentratiocombinatorics proposedcombinatorics

Problem Statement

In a school, more than 90%90\% of the students know both English and German, and more than 90%90\% percent of the students know both English and French. Prove that more than 90%90\% percent of the students who know both German and French also know English.
Back to ProblemsView on AoPS