Last month a phone company charged $ 0.07 per minute for the first 300 minutes of calling time and $0.05 per minute for each minute of calling time in excess of the first 300 minutes . for how many minutes of calling time was bob charged by the phone company last month? 1) last month the phone company charged bob $21.00 for his calling time that was charged at $0.07 per minute.2) last month the phone company charged bob $40.00 for his calling time that was charged at $0.05 per minute.