Oh statistics. From all math was toughest on me in school. (I mean advanced concepts like Statistical hypothesis testing) Thanks God such stuff is not tested on GMAT. Did you guys look into this thread statistics-rules-and-tips-69015.html
I think it has pretty much all the info.
Also there is a link to sample lesson by integrated learning on SD with some neat examples - http://www.integratedlearning.net/gmat/sample.asp
(BTW links can be found in New to the Math forum? Please read this first
Also you can try to visualise concepts yourself. Of course for that you have to truly understand them.
Like in a example given. What is SD? It's a measure of dispersion. Or whether numbers in set tend to be close to the mean (or not). So if SD is equal to 0 than all 10 numbers are the same number..
My Recent Posts:
All GMAT CAT Practice Tests - links, prices, reviews
Master thread - GMAT Prep classes links to reviews and ratings
Review: GMATPrep (GMAT Prep) & PowerPrep (Power Prep) Tests
Have trouble finding answers on this site? Ask me!