Rule of 72 Approximately how many years does it take to double a $500 investment when interest rates are 4% per year?
A) .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 the investment at a given annual interest rate. By dividing 72 by the interest rate (4%), you get 18 years.

Rule of 72 Approximately How Many Years Does It Take