Hello and welcome to money girls quick and dirty tips for a richer life.

Today's topic, the rule of 72.

I want to tell you about a cool little trick you can use to quickly estimate

the interest rate you would need to earn to double your money in a specific number of years.

Here's how it works.

Simply divide 72 by the number of years to get the interest rate you'd need to earn for your money

to double during that time.

Let's say you want your money to double in 10 years.

What interest rate would you need to earn?

All you need to do is divide 72 by 10. You'd need to earn a 7.2% interest rate for your money to double in 10 years.

And what if you wanted your money to double in 5 years. 72 divided by five is 14.4. You'd need to

earn 14.4% per year if you wanted your money to double in five years.

You can also use the rule of 72 backwards.

To estimate how long it will take for your money to double,

simply divide 72 by the interest rate.

For example, let's say you're having a super successful investing run and earning 20%

annually.

How long would your run need to last for your money to double?

Just divide 72 by 20. Your money would double in only 3.6 years.

Pretty nifty.

Okay, to recap, you can divide 72 by the number of years to get the interest rate or you can

divide 72 by the interest rate to get the number of years it will take for your money to double. The rule of

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