Issue placing three-divs; third div somehow affects whole page

Issue placing three-divs; third div somehow affects whole page

References

Reference NO 1

http://stackoverflow.com/questions/15190815/issue-placing-three-divs-third-div-somehow-affects-whole-page

Reference NO 2

http://stackoverflow.com/questions/15328799/undesired-offset-when-floating-divs-one-next-to-the-other

Reference NO 3

http://www.vanseodesign.com/css/3-column-layout-code/

Reference NO 4

http://www.webdeveloper.com/forum/showthread.php?265493-The-uncooperating-div

Reference NO 5

http://csswizardry.com/2011/08/building-better-grid-systems/

Reference NO 6

http://cssing.blogspot.com/2004/08/blocks-by-default-stack.html

Reference NO 7

http://html5insight.com/

Reference NO 8

http://coding.smashingmagazine.com/2011/08/23/the-semantic-grid-system-page-layout-for-tomorrow/