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Awesome averages.

Number Theory Level 3

What is the average (mean) of all 5-digit numbers that can be formed by using each of the digits 1, 3, 5, 7, 8 and exactly once?

Excel in math and science

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It's hard to learn from lectures and videos

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including olympiad champions, researchers, and professionals.

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by Shashank Rammoorthy

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