Business Math
posted by Jennie .
If your inital investment is $1000, and your rate of return is say 10%, did you make $100 or $1100 from your $1000?

The interest is your return, 100 dollars in the first year.

0.1 * 1,000 = ?
That's what you'll make on your investment.
Of course you'll also get the principle back as well as the interest. 
Is it certain that you will get the principle back for every kind of investment?

No. When you invest in junk bonds or stocks you are not guaranteed that you'll get all of your initial investment back.