You are considering opening a new plant. The plant will cost $102.5 million upfront and will take one year to build. After that, it is expected to produce profits of $29.5 million at the end of every year of production. The cash flows are expected to last forever. Calculate the NPV of this investment opportunity if your cost of capital is 7.8 %. Should you make the investment? Calculate the IRR. Does the IRR rule agree with the NPV rule?

I know the NPV is 248.34 million but I need to calculate the IRR and I need someone to really dumb it down step by step on how to calculate the IRR. I know the answer is 23.34% but how did they come up with that. Can you please detail this out both with and without excel?