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CEMC Gauss (Grade 7), 2011

Number theory Difficulty 2.0 Junior Find the answer Canada

Steve begins at 77 and counts forward by 33, obtaining the list 7,10,13,7, 10, 13, and so on. Dave begins at 20112011 and counts backwards by 55, obtaining the list 2011,2006,2001,2011, 2006, 2001, and so on. Which of the following numbers appear in each of their lists?

(A) 10091009 (B) 10061006 (C) 10031003 (D) 10011001 (E) 10111011

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