Can anyone help me figure out this riddle?

[cheerfulgreek]

Originally Posted by christiangirl

I got 4000 the first 3 times. I was adding in my head and well you do that, you get used to the first digit increasing (because it keeps going up by 1000) so when you get to that ten, you automatically carry the one to the 3, making it 4000, instead of carrying it to the 0. Just sloppy addition and paying to close attention to patterns than the actual math, that's all.

I did too. I think it's the message board. I'm almost positive it works better on paper. Everyone that I told about it said 4000. I've never seen anyone get 3100. With the exception of the GC members above.