How to calculate percentages is easier than you think. Quick, what’s 36% of 25? Or how about 250% of 20? Learn a quick and dirty tip to help you calculate all of those pesky percentages in your head.

Whenever you change something on a Microsoft Excel 2010 spreadsheet, the program will recalculate some of the cells in the worksheet, even some of those that did not change. Normally, Excel operates ...