Revision as of 01:15, 20 October 2014 by Timneh(talk | contribs)(Created page with "== Problem == Express the following sum as a whole number: <math>1+ 2 - 3 + 4 + 5 - 6 + 7 + 8 - 9 +10 +11-12 +\cdots + 2005 + 2006 - 2007.</math> == Solution == == See Also ...")