The formula is A=p (1+r/k)^kt A future value 30000 p present value 20000 R interest rate 0.15 K compounded quarterly 4 T time? 30000=20000 (1+0.15/4)^4t Solve for t Divide both sides by 20000 30000/20000=(1+0.15/4)^4t Take the log of both sides Log (30000/20000)=4t×log (1+0.15/4) Divide both sides by log (1+0.15/4) 4t=Log (30000/20000)÷log (1+0.15/4) Divide both sides by 4 T=(log(30,000÷20,000)÷log(1+0.15÷4))÷4 T=2.7 years round your answer to get 3 years