Marcia had been earning a monthly salary of $2500. She got a raise to $2600 per month. What percent raise did she get?

There are a few ways to compute this but my favorite is to focus on the amount of the raise.  It is fairly simple to see that she got a raise of $100 so we need to compare that raise to her previous salary of $2500. 

 

100/2500=0.04 so she got a 4% raise.

Well explained, jboy.

I gave you a thumbs up. :)