Question

Rani arrived at the library at 12:04 PM. She spent 52 minutes in the library before she left.

Answer 1

It is 12:04 when she arrives at the library. Add 50 mins to equal 12:54. Then add 4 to equal 12:56. She leaves at 12:56.

Answer 2

Rani arrives at 12:04 so lets make it easier and make it 12:00. She spends 52 mins so add 52 to 12:00 which is 12:52. Now add the 4 mins from before and you get 12:56
Hope this helped!