> How / what investments would yield a 10% return through interest.

Stock index funds can have 20 or 30 year averages in the 8-10% range but they are anything but steady and by no means guaranteed. Here is a page that lets you calculate returns on the S&P500 for different periods: http://www.moneychimp.com/features/market_cagr.htm

In practice paying off debt is the only certain way to get that high of a return.

>How do I apply this concept to my Roth IRA?

Don’t get too fixated on getting a specific return rate- that is something you generally can’t control unless you can save enough money that you can take the much lower guaranteed rates of return.

But here are some things I keep in mind for My Roth IRA:

Time is important make those investments as soon as you can.
Max the contributions if at all possible- it could make a huge difference in the quality of your retirement.

Taking a moderate risk to invest in stock index funds is likely to really pay off big.

Minimize fees- a 1% expense is really large! Even if you can’t control the market returns you can choose lower fee funds.

-Rick

Thanks!
Jack