Math to break into Investment Banking part 6/100 🧮: Net Present Value (NPV) vs Internal Rate of Return (IRR). NPV and IRR are the most important models in the financial industry to determine the value of projects and to decide which projects to accept. NPV uses the concepts of discounting cashflows. We use the weighted average cost of capital as our discount rate and discount all cashflows the project produces, including negative cashflows, to the present day. If NPV is positive --> Project inc