When a train travels at a speed of 60kmph,it reaches the destination on time.…
2024
When a train travels at a speed of 60kmph,it reaches the destination on time. When the same train travels at a speed of 50kmph, it reaches its destination 15min late. What is the length of journey?
Answer: A. 75 km — Let d be the length of the journey in kilometres. Time when travelling at 50 km/h = d/50 hours. Time when travelling at 60 km/h = d/60 hours. The train is 15…
- A.
75 km
- B.
60 km
- C.
85 km
- D.
50 km
Attempted by 13 students.
Show answer & explanation
Correct answer: A
Let d be the length of the journey in kilometres.
Time when travelling at 50 km/h = d/50 hours. Time when travelling at 60 km/h = d/60 hours.
The train is 15 minutes late at 50 km/h, so the difference in time is 15 minutes = 15/60 = 0.25 hours.
Set up the equation: d/50 - d/60 = 0.25
Compute the coefficient: 1/50 - 1/60 = (6 - 5)/300 = 1/300, so d × (1/300) = 0.25
Solve for d: d = 0.25 × 300 = 75 km
Therefore, the length of the journey is 75 km.