This website contains problems from math contests. Problems and corresponding tags were obtained from the Art of Problem Solving website.

Tags were heavily modified to better represent problems.

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Found problems: 27

2012 Purple Comet Problems, 4

How many two-digit positive integers contain at least one digit equal to 5?

2017 AIME Problems, 1

Find the number of subsets of $\{ 1,2,3,4,5,6,7,8 \}$ that are subsets of neither $\{1,2,3,4,5\}$ nor $\{4,5,6,7,8\}$.