Rule of 72 Approximately how many years does it take to double a $500 investment when interest rates are 4 percent per year?
A)0.06 years
B)6 years
C)6.94 years
D)18 years

Question

Quizplus · Accepted Answer

The Rule of 72 is a simple way to estimate the number of years required to double an investment at a given annual interest rate. By dividing 72 by the interest rate (4% in this case), you get 18 years.

Rule of 72 Approximately How Many Years Does It Take