"Look at these flags and tell me-" Said Grandpa flashing a paper with many Flags on it.
"Which one does not belong to the group? All, except one, have one interesting commonality. One property they all show except one," He continued.
"And before you tell me the obvious square one, let me be clear. It has nothing to do with the shape or size of the flag itself, whether it is a country flag or not, the colors or where the countries come from-- the geography I mean. And no obvious things like only Japan has a circle or Israel has a star. We all know each flag is a different design."
"That makes it hard to guess," I complained.
"Well. Here is a hint. The commonality kind of relates to a 3 digit number-- chew on that one" He said with a smile.
I am more confused. Which one is it and why?