Investment how long would it take to double your principal in an account that pays 6.5% annual interest compounded continuously

The formula for continuously compounded interest is the following:



Where is the resulting amount, is the initial amount, is the mathematical constant (2.718...), is the interest rate (percentage), and is the time in years.

Since you are looking to double your money, you can use any value for and , as long as is twice . This gives you the following equation:



Solving for will give you your answer.