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Arithmetic

Algebra Level 2

In an arithmetic sequence, the sum of the first and the third terms is 6, and the sum of the second and fourth terms is 20. Determine the fifteenth term of the sequence.

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 Benedict Dimacutac

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