Calvin Johnson has a $$$$5$ comma $500$ debt balance on his Visa card that charges $17\mathrm{.}4$ percent APR compounded monthly. In$2009,$ Calvin's minimum monthly payment is $3$ percent of his debt$$ balance, which is $$$$165.$ How many months$($round up$)$ will it take Calvin Johnson to pay off his credit card if he pays the current minimum payment of $ $165$ at the end of each$$ month? In$2010,$ as the result of a federal$$ mandate, the minimum monthly payment on credit cards rose to $4$ percent. If Calvin made monthly payments of $$$$220$ at the end of each$$ month, how long would it take to pay off his credit$$ card?