(1 + r)^n = 2
n = log(2) / log(1 + r)
Example: r = .06 (6%)
n = log(2) / log(1.06) = 11.89566.... ; not quite 12 years
Fred invests an amount of money in an account by paying r% compound interest per annum. The amount of money doubles after n years.
I'm aware of the compound interest formula A=P(1+r/100)^n however I have no idea how to change it according to n.
Would I start off along the lines of 2A=p(1+r/100)^n?