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, 2008

Number theory Difficulty 2.0 Junior Find the answer Canada

Suppose $N=1+11+101+1001+10001+\ldots+1\overbrace{000\ldots00}^{50\text{ zeroes}}1$ . When $N$ is calculated and written as a single integer, the sum of its digits is

(A) $58$ (B) $99$ (C) $55$ (D) $50$ (E) $103$

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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.