The IRR is the discount rate r that makes a project have an NPV of $0. You can find IRR in Excel with the built-in IRR function, using the syntax =IRR(range of cash flows). However, it can be tricky....

The IRR is the discount rate r that makes a project have an NPV of $0. You can find IRR in Excel with the built-in IRR function, using the syntax =IRR(range of cash flows). However, it can be tricky. In fact, if the IRR is not near 10%, this function might not find an answer, and you’ll get an error message. Then you must try the syntax =IRR(range of cash flows, guess), where “guess” is your best guess for the IRR. It’s best to try a range of guesses (say, -90% to 100%). Find the IRR of the project described in Problem 34.

Problem 34