Hey guys,
I came across this site a couple of nights ago and after reviewing it, found that it would be helpful to anyone taking the GMAT. The site pretty much wraps up all the PERM/COMB/PROB. concepts you'll need for the GMAT or that have been discussed in this forum.
Hope it helps.....
http://www.mansw.nsw.edu.au/members/...ol23no4yen.htm
PS: Please keep in mind that the GMAT is not a Discrete Maths exam, ie, you will see no more than 3-4 of these question on the exam, and thats if thy doing really well, so don't spend too much time on this topic.