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Algebra Level 3

What is the first digit of \(-5 + 12 - 19 + 26 - 33 + 40 - \ldots - 2007 + 2014 \)?

3 4 2 1

Excel in math and science

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It's hard to learn from lectures and videos

Learn more effectively through short, conceptual quizzes.

Our wiki is made for math and science

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including olympiad champions, researchers, and professionals.

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by Pi Han Goh

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