OK, here's a tough one! How many marbles are in the gallon size pickle jar that's sitting in the front window of Uncle Danny's Gourmet Deli? I'll split the prize with you if we win!
An example:
What makes it tough is that although we know the size of the jar the marbles within are of different sizes and so it's not just a matter of dancing with a bit of Archimedes' principle.
