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## 'Prison Cells' printed from http://nrich.maths.org/

There are seventy eight prisoners in a square cell block of
twelve cells. There is one prisoner in one of the cells, two in
another cell, three in another, four in another and so on up to
twelve prisoners in one of the cells.

The clever prison warder made it easy to check if the prisoners
were all there by arranging them so there were twenty five along
each wall of the prison block. How did he do it?

(There's more than one solution - send yours in - it might be
different to everyone else's!)

Here is an interactive game with which to experiment.

This text is usually replaced by the Flash movie.

In case the above version does not
work, here is another version.

This text is usually replaced by the Flash movie.

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