Postcardproblem 1

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 a rectangle in the centre, enclosed
by pentominoes.

The parts in our example are 36 squares.

The rectangle is even a square.

Name |
Country |

Edo Timmermans (48) |
the Netherlands |

Bob Henderson (45) |
USA |

Bob emailed a few challenges:

Try to make each area equal 54.

Try to make each area equal 56.

We think however that it can not.