Multiple choice

With a 9% compound interest rate, your money will double in

  1. 5 Years

  2. 6 Years

  3. 7 Years

  4. 8 Years
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Using the Rule of 72 for compound interest calculations, divide 72 by the interest rate to get the doubling time: 72/9 = 8 years. This is a close approximation for how long it takes an investment to double at a given compound interest rate. The exact calculation would be ln(2)/ln(1.09) which equals approximately 8.04 years.

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