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the letters 2

Discrete Mathematics Level 3

Aman wrote 7 letters. If there are 4 post offices in the city, in how many ways can he post the letters ?

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

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examples, and problems from the community.

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including olympiad champions, researchers, and professionals.

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by Sanskar kumar

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