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The Times & The Sunday Times
The Times & The Sunday Times
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Teaser 2762

A friend showed me a beautiful gem with shiny flat faces and lots of planes of symmetry
Michael Fletcher
The Sunday Times
Michael Fletcher
The Sunday Times

What a gem!

A friend showed me a beautiful gem with shiny flat faces and lots of planes of symmetry. After a quick examination I was able to declare that it was “perfectly square”. This puzzled my friend because none of the faces had four edges. So I explained by pointing out that the gem’s number of faces was a perfect square, its number of edges was a perfect square, and its number of vertices was a perfect square.

How many faces did it have, and how many of those were triangular?

Solution to Teaser 2760: 60 metres by 169 metres

Send your solution to Teaser 2762, The Sunday Times, 1 London Bridge Street, London, SE1 9GF or email puzzle.entries@sunday-times.co.uk. The first two correct solutions opened win £20.

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