A jogger running at 9 kmph alongside a railway track in 240 metres ahead of the engine of a 120 metres long train running at 45 kmph in the same direction. In how much time will the train pass the jogger?
Aptitude
Problems on Trains
Difficulty: Medium
Choose an option
-
A32 s
-
B34 s
-
C36 s
-
D38 s
Answer
Correct Answer: 36 s
Explanation
Given Data
- Jogger is 240 m ahead of the engine
- Train length = 120 m
- Speeds: train = 45 km/hr, jogger = 9 km/hr, same direction
- Required: time for the train to pass the jogger completely
Step 1: Relative speedvrel = 45 − 9 = 36 km/hr = 36 × (5/18) = 10 m/s
Step 2: Relative distance to coverGap to cover = 240 m + train length 120 m = 360 mt = 360 ÷ 10 = 36 s
Checks & Common Pitfalls
- Add gap + train length for complete passing.
Final AnswerThe train passes the jogger in 36 s.