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UKMT Senior Kangaroo, 2024

Combinatorics Difficulty 3.0 AMC 10/12 Prove it United Kingdom

Kevin begins with eleven stones and a mallet. Every time he hits a stone with the mallet it breaks into exactly eight pieces. Kevin keeps hitting stones with his mallet, but stops before he has 1000 stones. What is the largest number of stones he could end up with?

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