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Just for the sake of quizzes

Algebra Level 1

What is 40% of the quantity obtained when 1200 is subtracted by 50% of 800?

Excel in math and science

Master concepts by solving fun, challenging problems.

It's hard to learn from lectures and videos

Learn more effectively through short, conceptual quizzes.

Our wiki is made for math and science

Master advanced concepts through explanations,
examples, and problems from the community.

Used and loved by 4 million people

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including olympiad champions, researchers, and professionals.

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by Margaret Zheng

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