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Warmup Problem

Algebra Level 2

What is $99^2 - 98^2 \, ?$

Note: Try it without using a calculator.

199 187 197 198

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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.

Used and loved by over 7 million people

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including olympiad champions, researchers, and professionals.

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by Taru Bhardwaj

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