Check out my Math Variety blog posts on how to solve percentage problems like this. You’ll find a step-by-step method on how to do these problems, practice problems, and solutions.

http://mathvariety.blogspot.com/2009/04/percentage-problems.html

http://mathvariety.blogspot.com/2009/05/percentage-problems-practice-problems.html

http://mathvariety.blogspot.com/2009/05/percentage-problems-solutions-to.html

I also have an eHow article on this topic at http://www.ehow.com/how_4816051_solve-percentage-problems.html if you want to read it.

Start with x/100=is/of. Here, x=percent (unknown), is=22 ("is 22"), of=126 ("of 126"). We have:

x/100=22/126

Cross multiply:

x*126=100*22

126x=2,200

x=17.46 (rounded answer)