Math Help

I'm sharing this link in case anyone else can use the help.

http://plus.maths.org/index.html

I'm preparing for a promotional exam that will be given in a little less than a year (yes, I'm getting ready early). I googled "Math Refresher" to try and find some help. The exam has a section dealing with statistics and I've never taken a statistics class. While searching I found this NASA site (http://www-istp.gsfc.nasa.gov/stargaze/Smath.htm) which recommended the above link.