40. Symmetric Bridgechallenge
Roel Huisman from Portugal made this little symmetric bridge.

Build a bridge with the biggest area with a set of pentominoes.
Notice the rule used to join the 12 pentominoes is that they must touch along the full edge of the square and not just at the corners.
The bridge must have a symmetric inside border.

This will make finding a solution to the above problems easier:
PENTOMINO

Is your age between 12 and 18?
In that case you’ve get the chance to win a TI-84 Plus, if you send a best solution.

With many thanks to:Texas Instruments who sponsored us with the TI-84 Plus.
Prizes are allotted on April 30, 2008.

Send your solution to:
meulemeester50@gmail.com