Fast Typing Co. is in the business of manufacturing and selling Fast-Line Typewriters. It does not offer any credit sales currently. The per unit price and cost of each Fast-Line typewriter are \($900\) and \($600,\) respectively. Fast Typing Co. is considering the possibility of credit sales. The market price of the typewriter will stay the same with credit sales, but it is expected that the annual sales will increase from 5,000 units to 9,000 units and the per unit cost will go up by \($50\) due to implementation cost of credit sales. The credit period will be two months and the appropriate discount rate for the credit period is 1.5 percent.

What is the minimum probability of repayment that can make Fast Typing Co. indifferent between whether or not to implement the new credit policy?