At a 3% rate of interest, you will quadruple your money in approximately ____ years.

A) 3
B) 6
C) 12
D) 24
E) 47

To quadruple your money, you need it to grow to 4 times its original amount. Using the rule of 72, which is a simplified formula to estimate the number of years required to double the investment at a fixed annual rate of interest, you divide 72 by the interest rate. However, since we're looking to quadruple, not double, we need to adjust our calculation. Doubling twice equals quadrupling, so we calculate the doubling time and then multiply by 2. At a 3% interest rate, it takes 72 / 3 = 24 years to double. To quadruple, we need to double the money twice, so 24 * 2 = 48 years. The closest answer provided is 47 years, acknowledging some approximation in the rule of 72 and rounding.