Final answer:
Maria will arrive at her friend's house at 3:00 pm after completing her errands and drive.
Step-by-step explanation:
Maria needs to run a couple errands before meeting with her friend. She thinks she will spend 15 minutes at the post office, 1 hour and 25 minutes at the mall, and 20 minutes to drive to her friend's house. If Maria leaves her house at 1:00 pm, she can add the time for each activity to find the total time for her errands and drive. 1 hour 25 minutes + 20 minutes + 15 minutes = 1 hour 60 minutes. Since 60 minutes equals 1 hour, this will add 1 hour to the total number of hours. Therefore, Maria should arrive at her friend's house at 3:00 pm.