By Edo Timmermans.
Try to place the 12 pentominoes
inside the largest possible rectangle, in such a way that the pentominoes divide the rectangle in 5 parts of equal size.
There may not be more then 5 open areas; also open areas are not allowed to touch each other in a corner.
The pentominoes must form one shape, so that from any pentomino there is a pentomino path to any other pentomino.
Find the largest solution in which there is an open area in the centre, enclosed by pentominoes.
This Excel file
will make searching
for a solution a bit easier.
To download it click with the right mouse button and choose ‘Save target as ...’ to save this Excel file on your hard disk or diskette.