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An algebra problem by d w

Algebra Level 2

Every third digit is removed from the sum of the first 1000 positive integers. 1 + 2 + 4 + 5 + 7 + 8 + 10 + 11 + · · · + 998 + 1000 =x

What is x?

500500 333667 166833 889111

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Excel in math and science

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It's hard to learn from lectures and videos

Learn more effectively through short, interactive explorations.

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including olympiad champions, researchers, and professionals.

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