Solving for Interest: What annual rate would cause $200 to grow to $350 in 3 years? Solving for Period (N): If sales grow at 8% per year, how long before sales double? Current sales are 1%. Solving for Future Value (FV) of an Ordinary Annuity: What is the FV of a 3-Year Ordinary Annuity of $500 at 6% interest? Solving for Present Value (PV) of an Ordinary Annuity: What is the PV of a 3-Year Ordinary Annuity of $500 at 6%?