Hmm, my 89 and 92 say that the solution is ln(p(r/n + 1)) * n = ln(a) / t AND a >= 0 It isn't possible to solve it past that. Even Mathematica can't do it! > I managed to solve the equation A = P(1+r/n)^(nt) for everything but n... > > Is it even possible to solve this equation for n by some theorem or > property that I have not yet learnt.