To find the percent of change we will set up a proportion and solve it.  If you have trouble solving proportions, return to the Menu and click on the Proportion button.

The proportion is set up as follows:

Let's try an example:  Bob had 32 apples, but he ate 4 of them today.  What was the percent of change in the apples?

We must first find the change= - 4

Now find the original# (number we started with) =  32

Plug those numbers into the equation and it looks like this:

Solve like a proportion; (Cross multiply & divide)                   
(4)(100) = 32

400  = 32r

12.5 = r Therefore, the percent of change was 12.5% decrease in the number of apples.