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​(Annuity payments) Calvin Johnson has a
​$5,000
debt balance on his Visa card that charges
14.2
percent APR compounded monthly. In​ 2009, 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 2010, 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?