Question

Using the rule of 72, if you invest $1,000 at an annual rate of 8%, about

how long will it take to double your investment?

Answer 1

Answer: 10

Explanation:

time to double = 72/rate(as a percentage)

= 72/7

≈ 10.29

It will take about 10 years for your investment to double.

Answer 2

9

Explanation:

it will take approximately (72 / 8) = 9 years to double the invested money.