I was looking at your logic puzzles and there is one about "Marble Mix Up" that is totally incorrect, i suggest you guys take it off. There are two solutions to the problem, and the solution given is not one of them. I was looking at this because i teach a logic class for 8th graders and was looking for problems. I can give you the two solutions if you want them, but there are 2 correct answers for this problem. Also, there are 3 answers for the one about 4 people travelling by 4 means of transportation. Only one of the possilbe 3 answers is given. Okay, thanks.