Maths Olympiad Prep

Library / CEMC Pascal /399 of 603

CEMC Pascal, 2011

Algebra Difficulty 2.0 Junior Find the answer Canada

In the diagram, there are 26 levels, labelled A,B,C,…,ZA, B, C, \ldots, Z. There is one dot on level AA. Each of levels B,D,F,H,J,…,B, D, F, H, J, \ldots, and ZZ contains twice as many dots as the level immediately above. Each of levels C,E,G,I,K,…,C, E, G, I, K, \ldots, and YY contains the same number of dots as the level immediately above. How many dots does level ZZ contain?

(A) 10241024 (B) 20482048 (C) 40964096 (D) 81928192 (E) 1638416384

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