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Cross Junction

Discrete Mathematics Level 3

In the figure above with 9 squares, how many ways are there to select two squares which do not share an edge?

This problem is part of the set Countings.

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,
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including olympiad champions, researchers, and professionals.

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View solutions

by Nihar Mahajan

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