Answer:
School ended at 3:20 pm
Explanation:
The school ended at the same time as the final bell. We will call this time "x". After 20 minutes the practice began, therefore it began at "x + 20 min" and it lasted for 30 min, therefore it ended at "x + 50 min". She took an additional 15 minutes to get home, therefore she got home at "x + 65 min" or "x + 1h05min". We know that she arrived at 4:25, so:
x + 1:05 = 4:25
x = 4:25 - 1:05
x = 3:20 p.m.
School ended at 3:20 pm