I was asked to create a bell curve in excel and i didn't know how to do it, so i googled it out and followed the instructions on MS's website.

http://support.microsoft.com/kb/q213930/

Here is the output:

http://img99.imageshack.us/img99/217/bellcurveyz6.jpg

You can't see it all, but Column A is the original data (it's 75 data points) and column D is random numbers generated from this data (it's 2000 data points).

The blue curve seems to be the normal distribution. The other 2 curves, i have no idea what that is. Does anyone know which curve represents the actual data? Thanks!