This is a problem with mutually exclusive projects. You only have to do the net present value method, so you can evaluate the projects separately, or...

This is a problem with mutually exclusive projects. You only have to do the net present value method, so you can evaluate the projects separately, or you can combine them. But if you evaluate them separately, the answer you submit must be the difference in the two net present values (see the directions for the correct sign to use). As you determine the cash flows, make sure that you use the correct project life and that you treat the current disposal value of the current machines properly. And finally, read everything very carefully; some costs are expressed per machine, some for all machines, some monthly, and some annually.

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