Hi,
Welcome to Pagalguy. The posts in Pagalguy are divided into different threads. The answer related to your question have already been answered many times in the following threads:
http://www.pagalguy.com/forum/gmat-a...entre-108.html (GMAT Query Centre)
http://www.pagalguy.com/forum/gmat-a...terial-84.html (GMAT Prep Material)
Please do not open new threads for such questions. You can use the "search" feature for existing threads.
Thanks.