Work backwards — AMC & AIME Problems

Practice every real AMC 8, AMC 10, AMC 12, and AIME problem that uses Work backwards — a problem-solving techniques 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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AMC 8

1987 AMC 8 Problem 15 1987 AMC 8 Problem 18 1990 AMC 8 Problem 21 1991 AMC 8 Problem 21 1996 AMC 8 Problem 12 1998 AMC 8 Problem 25 2002 AMC 8 Problem 25 2005 AMC 8 Problem 1 2005 AMC 8 Problem 24 2009 AMC 8 Problem 1 2010 AMC 8 Problem 21 2013 AMC 8 Problem 6 2020 AMC 8 Problem 22

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