Answer:
55 minutes
Explanation:
This is quite a simple question, all its asking you to do is calculate how long the train journey took by using its departure and arrival times.
The train left at 10:20
The train arrived at 11:15
We know that if the train journey took one hour it would arrive at 11:20, however we have been told that the journey actually took five minutes less if it arrived at 11:15
60 minutes are in an hour, let's use this
60 - 5 = 55 minutes!