Question
If you want to double your investment of $1,200 using a savings account with a 6% annual interest rate compounded annually, how many years will it take?
Ask by Norris Pollard. in South Africa
Jan 07,2025
Upstudy AI Solution
Tutor-Verified Answer
Answer
It will take approximately 12 years to double the investment of $1,200 with a 6% annual interest rate compounded annually.
Solution
To determine how many years it will take to double an investment of $1,200 with a 6% annual interest rate compounded annually, we can use the formula for compound interest:
Where:
-
is the amount of money accumulated after n years, including interest. -
is the principal amount (initial investment). -
is the annual interest rate (in decimal form). -
is the number of times that interest is compounded per year. -
is the time the money is invested for in years.
Given:
-
-
-
(compounded annually) -
(double the initial investment)
We need to solve for
when
.
Solve the equation by following steps:
Solve the equation by following steps:
- step0: Solve for
:
- step1: Simplify:
- step2: Multiply by the reciprocal:
- step3: Multiply:
- step4: Take the logarithm of both sides:
- step5: Evaluate the logarithm:
The number of years it will take to double the investment of $1,200 with a 6% annual interest rate compounded annually is.
Answered by UpStudy AI and reviewed by a Professional Tutor
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Mind Expander
To double your investment of $1,200 at a 6% annual interest rate compounded annually, you’ll use the Rule of 72. This handy rule states that you can estimate the number of years to double your investment by dividing 72 by the annual interest rate. In this case, 72 ÷ 6 = 12. So, it will take approximately 12 years to double your money!
While the Rule of 72 provides a quick estimate, you can also use the formula for compound interest for a precise answer. The equation A = P(1 + r)^n (where A is the amount of money accumulated after n years, P is the principal amount, r is the annual interest rate, and n is the number of years) tells you more about the growth of your investment over time. Just set A to $2,400 (double your $1,200) and solve for n!