well when you try and find out how much the percentage has increased by you take the number its increased to divided by the number it was
e.g.
the number it increased to was 9.6 million and the number it was is 1.1 million
and to get the answer in a percentage you multiply by 100
try it with any number you will see what i am talking about

In the text book, " You find the difference between the two values. Next, put the original value in the bottom." You want to find the percent." Put a denominator of 100 (100%0 and a variable ( X ) as numerator