Question

This problem has multiple parts.

The rule of 72 states that if an investment earns P% interest per year, it will take approximately 72/P years for your money to double.

You invest 9185 at 3.3 % interest annually.

1. According to the rule of 72, what is the doubling time, in years, for this investment?

2. Use the doubling time to find a formula for V(t), the value of your investment at time t.

3. According to the doubling time, how much will your investment be worth after 49 years?

4. Use the compound interest formula to find how much the investment will be worth after 49 years.