You have 15 pool balls arranged in a triangle.

What is the greatest number of balls you will ever have to swap in order to ensure that they are all in the correct position at the start of the game?

An allowable position is either the one in the diagram above, the same position mirrored left-to-right, or either of these arrangements with the red and yellow balls switched.

I don't think some of you arn't really thinking about it, or even looking at the picture. One of you said 15. That can't posibly be right. 15 is too many. You might have to move them 14 times wich is what I thought at first but then i looked at the italic letters, and then at the picture, and that makes me think that the answer this person is looking for is 7. There are 7 red balls in the picture and there are 7 yellow balls in the picture GET IT!

Posted by Joy on 2005-05-28 01:20:34