An online retailer sells prepaid cell phone cards worth 500 minutes for $30 each. jayda can buy the card with no additional tax, but she will lose any minutes left unused at the end of the 30 days for which the card is active. what is the least number of the 500 minutes on the prepaid card jayda must use for the prepaid card to be cheaper than paying by the minute on her current cell phone plan? round your answer up to the higher full minute.