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Mindreader

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Weekly Problem 47 - 2009

Stage: 2 and 3 Short Challenge Level: Challenge Level:1
The square numbers around $1871$ are $42^2=1764$, $43^2=1849$ and $44^2=1936$. The only realistic possibility is that de Morgan was $43$ in the year $1849$, which puts his date of birth at $1806$.

This problem is taken from the UKMT Mathematical Challenges.

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