Description: In this example we grow a whole number by a percentage of itself. Growing by percentage is a common skill often used when figuring how much is owed or earned with interest. Let's say that I start this year in my stock portfolio with $95.00. And I say that my portfolio grows by, let's say, 15%. I think you might be able to figure this out on your own, but of course we'll do some example problems, just in case it's a little confusing.*Teacher Advisor is 100% free.