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Puzzle for Today

Puzzle No. 90 – Friday November 3

Alien bees invade Earth. On the third and fourth days of its life, each bee gives birth to a live clone, then dies at the end of its fourth day. The invasion begins with one bee. How many bees are there at the end of the twentieth day?

Today’s #PuzzleForToday has been set by Dr Gihan Marasingha, Senior Lecturer in mathematics at the University of Exeter

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