Counting intersections — AMC & AIME Problems
Practice every real AMC 8, AMC 10, AMC 12, and AIME problem that uses Counting intersections — a combinatorics concept — each with a professionally curated solution, many with a video solution too, from LIVE by Po-Shen Loh. Browse all concepts or the full past-contest archive.
All problems are used with official legal permission of the Mathematical Association of America (MAA).
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These problems’ difficulty ratings come from real solve attempts on our platform. Tap a band or a contest to filter the list below, and tap a selected band again to include all difficulties. See the full difficulty guide.
AMC 8
AMC 10
2001 AMC 10 Problem 4 • 2002 AMC 10B Problem 18 • 2010 AMC 10A Problem 22 • 2013 AMC 10A Problem 25 • 2019 AMC 10A Problem 10 • 2019 AMC 10A Problem 14 • 2021 AMC 10B Fall Problem 21
AMC 12
1963 AMC 12 Problem 27 • 1965 AMC 12 Problem 4 • 1968 AMC 12 Problem 30 • 1969 AMC 12 Problem 18 • 1970 AMC 12 Problem 26 • 1971 AMC 12 Problem 17 • 1973 AMC 12 Problem 29 • 1976 AMC 12 Problem 28 • 1981 AMC 12 Problem 18 • 1983 AMC 12 Problem 2 • 1985 AMC 12 Problem 10 • 1985 AMC 12 Problem 19 • 1999 AMC 12 Problem 12 • 2002 AMC 12B Problem 14 • 2007 AMC 12A Problem 24 • 2012 AMC 12A Problem 25 • 2014 AMC 12A Problem 24 • 2018 AMC 12B Problem 24 • 2019 AMC 12A Problem 8 • 2021 AMC 12B Fall Problem 19 • 2025 AMC 12B Problem 24