steps1 calculate the payback period which is given by the initial investment divided by operating cash flow

=10,500/19932=0.5268

step2.Find from the Present value interest factor annuity (PVIFA) tables for the life of the project,the PVIFA closest to the payback period you have calculated in step 1 above

step3.The discount rate associated with the factor is the projects internal rate of return,according to my table the closest is 99.99%