Calvin Johnson has a $5,000 debt balance on his Visa card that charges 12.9 percent APR compounded monthly. In 2005, Calvin’s minimum monthly payment is 3 percent of his debt balance, which is $150. How many months (round up) will it take Calvin Johnson to pay off his credit card if he pays the current minimum payment of $150 at the end of each month? In 2006, as the result of a federal mandate, the minimum monthly payment on credit cards rose to 4 percent. If Calvin made monthly payments of $200 at the end of each month, how long would it take to pay off his credit card?