You are operating an old machine that is expected to produce a cash flow of $5,000 in each of the next 3 years before it fails.

You are operating an old machine that is expected to produce a cash flow of $5,000 in each of the next 3 years before it fails.  You can replace it now with a new machine that costs $20,000 but is much more efficient and will provide a cash flow of $10,000 a year for 4 years. Should you replace the equipment now?  The discount rate is 15 percent. Show your work.