I am a a student in the 12th grade. I need to know how to calclulate the following: A percentage increase from 2.0% to 9.5% is what percentage?

Hi Ann,

If a quantity changes from a first value to second value then the percentage change is the difference, as a percentage of the first value. This sounds complicated. Let's look at an example
   Suppose that you are working for me selling books. I am going to pay you 2% of the value of the books you sell. You sold $1000.00 worth of books so I am to pay you 2% of $1000, that is (2/100)x$1000 = $20.00. You did so well that I have decided to increase your commission by paying you 9.5% of the sales you make, that is 9.5% of $1000 or (9.5/100)$1000 = $95.00.
   Thus your salary has increased from $20.00 to $95.00, that is an increase of $75.00. As a fraction of your starting salary this is 75/20 = 3.75 or 375%.
   Notice that this percentage increase of 375% does not depend on the $1000. If you had sold $x worth of books then the percentage increase would be

That is 375%.

Cheers,
Harley