Annabell invested $2000 into an account earning 3.5% interest compounded continuously. how long will it take to double her investment?

will become in 19.80 years that is approximately 20 years when compounded continuously at the annual interest rate of

Solution:

Given that  

Amount investe by Annabell = ,

Rate if interest  

And most important thing that interest is compounded continuously . Formula of Amount where interest is compounded continuously is as follows ,

Where A is final amount,  

P is principal Amount,

r = rate of interest  

And t = duration in years

In our case  

Need to evaluate t that is number of year.

On substituting given values in formula of amount we get

Taking log both the sides,  

That is approximately 20 years.