Library / UKMT Hamilton Olympiad /10 of 24

UKMT Hamilton Olympiad, 2018

Number theory Difficulty 3.0 AMC 10/12 Prove it United Kingdom

How many nine-digit integers of the form 'pqrpqrpqr' are multiples of 24? (Note that $p$ , $q$ and $r$ need not be different.)

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