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AMC modular arithmetic problems

Remainders, congruences, parity, units digits and modular exponentiation.

179 problems in the archive use these ideas — 102 from the AMC 10 and 77 from the AMC 12.

Picks a problem you have not seen, at about the difficulty you are handling.

60 most recent problems

Newest contests first. Every problem opens with its answer choices, hints and a worked solution.

Use Start modular arithmetic practice above to keep going through the remaining 119, or browse them by contest in the AMC 12 and AMC 10 archives.

Back to all number theory problems.