Question

Find the principle needed to have a balance of $1000 after 10 years invested at 3.25% interest compounded continuously

Answer 1

You will need to use this formula
Principal = Total / [e^(rate*years)]
(where "e" is the mathematical constant 2.718281828459)
Principal = 1,000 / [e^.0325*10]
Principal = 1,000 /  1.384030646
Principal = 722.53

Source:
http://www.1728.org/rate2.htm