Correct
Explanation
In the back. The train will be accelerating so it will be going faster when the back of the train enters the tunnel, so a person in the back will spend less time in the tunnel.
Solve this puzzle
Tom was on the way to the park. He met a man with 7 wives and each of them was with 7 kids. So, in total, how many were going to the park?
49 50 1 2