A firm is considering an investment in a new machine with a price of £32 million to replace its existing machine. The current machine has a book value of £8 million and a market value of £9 million. The new machine is expected to have a 4-year life, and the old machine has 4 years left in which it can be used. If the firm replaces the old machine with the new machine, it expects to save £5 million in operating costs each year over the next 4 years. Both machines will have no salvage value in 4 years. If the firm purchases the new machine, it will also need an investment of £500,000 in net working capital. The required return on the investment is 10 per cent, and the tax rate is 39 per cent.

(a) What are the NPV and IRR of the decision to replace the old machine?

(b) The new machine saves £32 million over the next 4 years and has a cost of £32 million.
When you consider the time value of money, how is it possible that the NPV of the decision to replace the old machine has a positive NPV?