...and if you solve this one be sure to write it up and let us know won't you. For what it's worth in my experience on both sides of the interview panel you've

...and if you solve this one be sure to write it up and let us know won't you. For what it's worth in my experience on both sides of the interview panel you've basically made an 80-90% decision on a candidate in less than 5 minutes (probably less than 1 in most cases). Everything that follows is gathering information to support that decision and maybe, just maybe push on that 10-20%.