Question

question 4 of 10
suzette opened a cd 10 years ago at an interest rate of 8.2%. according to the rule of 72, when did she have half as much money as she does now?
a. about 8.2 years ago
b. about 4.1 years ago
c. about 4.4 years ago
d. about 8.8 years ago

Explanation:

Step1: Find doubling time via Rule of 72

$\text{Doubling Time} = \frac{72}{8.2} \approx 8.78$ years

Step2: Relate to half current value

If the money doubles in ~8.8 years, then half the current amount was present 8.8 years ago (since it took that time to double to today's value).

Step3: Match to option

The calculated value matches option D.

Answer:

D. About 8.8 years ago