PV = PMT/i The goal is to solve the formula for i, doing so by isolating it to one side of the equation. The first step would be to cross multiply: PV/1 = PMT/i PV Solution PV = PMT/i The goal is to solve the formula for i, doing so by isolating it to one side of the equation. The first step would be to cross multiply: PV/1 = PMT/i PV.