Which number is the odd one out 7158 3129 6159 5149 2126 8113 4106?

That depends: How do you determine odd one out? 7158 is the only one with a last diget that is not divisable by 3, 4106 has a 0 while the others don't, and so on. Every number has one way in which it is different from all the others. Someone with a high IQ and a lot of time to waste can find a way to single out every number, I just don't think it would be worth the time.