Like many college students, Julie applied for a credit card that has an annual percentage rate of 18%. The first thing she did was buy a new stereo system for $250. At the end of the month, her credit card payment said that she only needed to make the minimum payment of $15. Assume Julie makes her payment when she sees her statement at the end of each month. If Julie doesnt charge anything else and only makes the minimum monthly payments, approximately how many months will it take for her to completely pay off the stereo system? Assume that the credit card company compounds interest at the end of the month.

Julie now realizes that she needs to pay more than just the minimum payment, so she pays twice the minimum payment per month ($30 per month) instead. How much quicker will she pay off the stereo system?

If instead, Julie wants to pay off the stereo system by the end of the year, what is the minimum monthly payment she must make?