I have a very basic understanding of standard deviation but apparently I need more. I've taken both of the GMATPrep tests and both times a standard deviation question appeared near the beginning. And both times I was stumped.
Pretty much all I know about standard deviation is that it is a way to express how far away from the mean a value is. But I don't understand how to manipulate it or how other numbers would affect it. The first question on the quantitative section was something like I had a certain set of numbers and the mean was 33. Then what numbers would need to be added to change the standard deviation. Obviously that's not exactly it but that is the kind of information I'm clueless about.
Can someone point me to a resource that will help me gain a basic understanding of this concept?
Pretty much all I know about standard deviation is that it is a way to express how far away from the mean a value is. But I don't understand how to manipulate it or how other numbers would affect it. The first question on the quantitative section was something like I had a certain set of numbers and the mean was 33. Then what numbers would need to be added to change the standard deviation. Obviously that's not exactly it but that is the kind of information I'm clueless about.
Can someone point me to a resource that will help me gain a basic understanding of this concept?
Last edited by allenkt on Mon May 07, 2007 6:41 am, edited 1 time in total.
