I am hoping to better understand the payback period formula and application. Here is the equation from the textbook Payback = Number of years prior to full recovery + (unrecovered cost at start of the year / cash flow during full recovery year Here is the equation from the PDF slide PBP= Years Before Full Recovery + (Uncovered Cost at the Start of Last Year) / (Cash Flow During the Year) Why is the uncovered cost at the start of the year divided by the cash flow during the year? Also, looking at Figure 10-9 specifically, does the payback value of 5.00 matter to firms looking at payback period?