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In the local wood there are a number of trees. On these trees there are a number of birds.
A local bird spotter knows that there are as many birds on each tree as there are trees in the wood, and that there are between 2,000 and 2,100 birds in total.
How many trees are there in the wood?
Puzzle Copyright © Kevin Stone
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Answer
45 trees.
Reasoning
We are after a number whose square lies between 2,000 and 2,100.
45 is the only possible number.