Number base — AMC & AIME Problems
Practice every real AMC 8, AMC 10, AMC 12, and AIME problem that uses Number base — a arithmetic 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).
Filter by difficulty
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 10
2003 AMC 10A Problem 20 • 2013 AMC 10A Problem 19 • 2013 AMC 10B Problem 25 • 2015 AMC 10A Problem 18 • 2018 AMC 10A Problem 18 • 2019 AMC 10A Problem 18 • 2019 AMC 10B Problem 12 • 2020 AMC 10A Problem 21 • 2021 AMC 10A Spring Problem 11 • 2021 AMC 10B Spring Problem 13 • 2021 AMC 10A Fall Problem 12 • 2022 AMC 10B Problem 25 • 2024 AMC 10A Problem 18 • 2025 AMC 10B Problem 4
AMC 12
1957 AMC 12 Problem 19 • 1959 AMC 12 Problem 19 • 1960 AMC 12 Problem 16 • 1961 AMC 12 Problem 17 • 1961 AMC 12 Problem 35 • 1962 AMC 12 Problem 22 • 1965 AMC 12 Problem 15 • 1965 AMC 12 Problem 33 • 1966 AMC 12 Problem 39 • 1967 AMC 12 Problem 16 • 1968 AMC 12 Problem 33 • 1969 AMC 12 Problem 3 • 1970 AMC 12 Problem 23 • 1971 AMC 12 Problem 11 • 1973 AMC 12 Problem 6 • 1974 AMC 12 Problem 28 • 1978 AMC 12 Problem 14 • 1981 AMC 12 Problem 16 • 1982 AMC 12 Problem 26 • 1999 AMC 12 Problem 25 • 2004 AMC 12A Problem 25 • 2005 AMC 12A Problem 19 • 2007 AMC 12B Problem 21 • 2012 AMC 12A Problem 20 • 2012 AMC 12B Problem 11 • 2013 AMC 12B Problem 23 • 2018 AMC 12A Problem 13 • 2019 AMC 12A Problem 11 • 2020 AMC 12A Problem 19 • 2021 AMC 12A Fall Problem 10 • 2022 AMC 12B Problem 23 • 2024 AMC 12A Problem 11 • 2024 AMC 12B Problem 6 • 2025 AMC 12B Problem 4
AIME
1986 AIME Problem 7 • 1989 AIME Problem 14 • 2000 AIME II Problem 14 • 2001 AIME I Problem 8 • 2003 AIME I Problem 13 • 2004 AIME II Problem 10 • 2008 AIME II Problem 4 • 2010 AIME I Problem 10 • 2012 AIME I Problem 5 • 2012 AIME II Problem 7 • 2014 AIME II Problem 15 • 2017 AIME I Problem 5 • 2017 AIME II Problem 4 • 2018 AIME I Problem 2 • 2018 AIME II Problem 3 • 2020 AIME I Problem 3 • 2020 AIME II Problem 5 • 2022 AIME I Problem 2 • 2023 AIME II Problem 2 • 2023 AIME II Problem 15 • 2024 AIME II Problem 6 • 2024 AIME II Problem 14 • 2025 AIME I Problem 1 • 2026 AIME II Problem 4