Maths Olympiad Prep

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, 2026

Algebra Difficulty 2.0 Junior Find the answer United Kingdom

Ada likes adding numbers! On Monday she added all the three-digit numbers each of whose digits is either 00 or 11. On Tuesday she added all the two-digit numbers each of whose digits is either 22 or 33. On Wednesday she added her answers from Monday and Tuesday. What was the result of Ada’s final addition?

(A) 310310 (B) 421421 (C) 532532 (D) 643643 (E) 754754

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