If Brian's brother took the boys to the mall at 11:30 AM and left at 1:45 PM, how much time did the boys spend at the mall?

2 hours and 15 minutes.

Step-by-step explanation:

Add 30 to 11:30 to 12:00. Add 45 to that to get 1 hour and 15 minutes. Then add the other hour.

2 hours 15 minutes

Step-by-step explanation: 45 - 30 is 15 so now you just have to subtract the hours and since 11:00 only goes to 12 you would go to one after that so 1:00 is like 13 so 11 - 13 = 2 so your answer is 1 hours and 15 minutes