How long will it take to triple your investment if the interest rate per year is 9%, and interest is paid only at the end of each year?
A)13 years
B)15 years
C)11 years
D)17 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 rate of return. By dividing 72 by the annual rate of return, investors can get a rough estimate of how many years it will take for the initial investment to duplicate itself. In this case, to triple an investment at a 9% interest rate, we can modify the rule slightly. Doubling the investment would take approximately 72 / 9 = 8 years. Tripling would take longer, but since only one option is close to being reasonable given the exponential growth nature of compound interest, 13 years is the best estimate without doing the exact calculation. The exact calculation involves using the formula for compound interest, but given the options and the nature of the question, a detailed calculation isn't necessary to select the most reasonable answer.

How Long Will It Take to Triple Your Investment If