In a square of side 4, I pack 4 circles of unit radius.

What's the largest circle I can fit into the center (such that it doesn't overlap the other circles)?

(In reply to Tessellation by e.g.)

Length of the Diagonal=√2+ 1+ diameter of red circle(x)+ 1+ √2

so 4√2=2+2√2+x

then x=2√2-2 (diameter of red circle)
so the red circle should be of radius √2-1

Posted by Surender Taalla on 2004-01-13 14:50:14