Wally loves your analysis. He has now asked you to evaluate potential new project investments. Both projects aim to make widgets. Widgets sell for $10 each. Project A will produce 4,500 units in the first year, 6,500 units in the second and third years and a whopping 44,000 units in the fourth year. Project A requires an investment of 7 machines each costing $50,000. Project B will produce 2,400 units in the first year, 2,200 units in the second year, 1,950 units in the third year and 1,460 units in the fourth year. Project B requires an initial investment of 1 machine worth $50,000. Wally has said that to make the analysis easier you need not calculate depreciation on the machine, the tax shelter benefit or the residual value of the machine at the end of production. Wally just said I want you understand the cash flows from the information provided above.

What is the discounted payback period for each project

please write it in detail with formula.