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It's combinatorics, wait a second!

Discrete Mathematics Level 2

How many ways can you arrange 30 people on a ferris wheel with 30 seats?

\[30!\] \[28!\] \[31!\] \[29!\]

Excel in math and science

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It's hard to learn from lectures and videos

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Our wiki is made for math and science

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including olympiad champions, researchers, and professionals.

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by Raghav Gupta

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