Maths Olympiad Prep

Library / /210 of 387

, 2008

Number theory Difficulty 2.0 Junior Find the answer Canada

If xx and yy are two-digit positive integers with xy=555xy = 555, what is x+yx+y?

(A) 5252 (B) 116116 (C) 6666 (D) 555555 (E) 4545

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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.