the answer is not 9 nor 9.3

(Solving for n with non-annual periods) Approximately how many years would it take for an imvestrnent to grow fourfold if it were invested at 16 percent comipounded manthly? Assume that you inwost $1 today. H you imves 51 at 16 percent compounded monthly, about how many years would a take for your investment to grow fourfold to 34 ? (Hint. Remenber to convert your calcilater bohition to years.) yeass (Round to one decimal place)