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pages of books

Algebra Level 2

Sophia finished \(\dfrac23\) of a book. She calculated that she finished 90 more pages than she has yet to read. How long is her book?

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

Learn from a vibrant community of students and enthusiasts,
including olympiad champions, researchers, and professionals.

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by lorenz navales

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