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An algebra problem by Mahmdullah Khaliq

Algebra Level 1

When I am 10 years old, my sister is half my age.
When I am 100 years old, what will be my sister's age?

Excel in math and science

Master concepts by solving fun, challenging problems.

It's hard to learn from lectures and videos

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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 Mahmdullah Khaliq

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