Question

what interest rate is necessary in order to have any amount double in 5 years assuming monthly compounding

Answer 1

Present value = $ 1

Future value : $2     [1*2]

number of months = 5*12 =60

Interest rate : [Future value /present value ]^1/n   -1

            =[2 /1]^1/60     -1

           = [2]^.016667    -1

          = 1.0116197-1

         = .0116197 or 1.16197 % monthly

Annual rate: 1.16197*12 = 13.94% annually