Lauren reads in the library for 1 hour 15 minutes. She leaves the library at 3:23 pm. at what time did she arrive?

You can answer this problem by solving backwards. she read for 1 hour and 15 minutes so start with 1 hour before she left. 1 hour before 3:23 is 2:23. Now subtract the 15 minutes from that 15 minutes before 2:23 is 2:08.

Therefore the time is 2:08pm.