The use of percentages in Excel are not the easiest concept to understand.
The percentages you use with Excel are just the same as the ones you might calculate with a calculator but it helps if you think about them slightly differently when calculating in Excel.
Always enter a percentage in Excel as a number followed by a percent sign. If you work this way, you don't have to worry about all that multiplying and dividing by 100!
Try these short tutorials - the easier ones are at the top...
(What is 7% of 2,500?)
(Increase 24,000 by 4%)
(Calculate a discount of 9% on a purchase of 120)
(7 answers out of 12 were correct. What is the percentage score?)
(Customer numbers changed from 2,800 to 3,200. What percentage increase is that?)
(Customer numbers changed from 3,500 to 3,400. What percentage decrease is that?)