Each 1/4 of an hour is 15 minutes, or one quarter because it is 1/4 of an hour. So a “quarter to three” means you will have to advance the time 15 minutes until reaching 3 o’clock. At 2:45, you will have to advance 15 minutes (1/4 or one quarter of an hour) to reach 3 o’clock. Answer: 2:45.
: 15 minutes before (a stated hour) It is now (a) quarter to four.