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Algebra Difficulty 1.9 Junior Find the answer

What is the value of 1+3+5++2017+2019246201620181+3+5+\cdots+2017+2019-2-4-6-\cdots-2016-2018?

Pick one

Solution

Rearranging the terms, we get (12)+(34)+(56)+...(20172018)+2019(1-2)+(3-4)+(5-6)+...(2017-2018)+2019, and our answer is 1009+2019=(E) 1010-1009+2019=\boxed{\textbf{(E) }1010}.
If you were stuck on this problem, refer to AOPS arithmetic lessons.
~Nivaar

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.