Title: 9-My paper By: Yanyan Chen 1 of 2 E Projects must have a payback period of less than three years Here are some estimates of the net present value of a project using different interest rates: Discount rates 6% 5% 4% 3% 42 2% 87 pair of interest rates will provide the most accurate estimate if interpolation is used to estimate the project's internal rate 5% and 6% 3% and 4% NPV -180 -110 -30