Even if you hated math as a student, you’ll love learning the Rule of 72; it takes less than a minute to learn. The Rule of 72 explained simply is an easy, yet powerful mental shortcut to quickly estimate how long it takes for money (or debt) to double. For example, if someone asked you how long it would take for their mutual fund to double in value if it's compounding at 10%, you'll be able to tell them within seconds without the use of a calculator. The Rule of 72 is my fav