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Birthday Problem!

Algebra Level 4

\[\large\sum _{ n=1 }^{ \infty }{ \frac { 6n }{ { 4 }^{ n } } }= \ ? \ \]

Give your answer to 2 decimal places.

Excel in math and science

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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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by Swapnil Das

Practice math and science questions on the Brilliant iOS app. Practice math and science questions on the Brilliant Android app.

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