Question

Using the rule of 72, how long will it take for the principal to double with an annual compound interest rate of 6%?

A. 6
B. 9
C. 12
D. 15

Answer 1

C. 12

Explanation:

With the rule of 72, you would divide 72 by the periodic interest rate to get the number of years for the principal to double

72 ÷ 6 = 12