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, 2005

Algebra Difficulty 2.0 Junior Prove it Canada

John and Mary wrote the Euclid Contest. Two times John's score was $60$ more than Mary's score. Two times Mary's score was $90$ more than John's score. Determine the average of their two scores.

Want a route through all this instead of an archive? The track puts 2,604 problems in a working order, from Junior Challenge level to the IMO shortlist.

Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project. Solutions are the publisher's, linked not copied.