Two trains, each 100 m long, moving in opposite directions, cross each other in 8 seconds. If one is moving twice as fast the other, then the speed of the faster train is:
Aptitude
Problems on Trains
Difficulty: Medium
Choose an option
-
A45 km/hr
-
B54 km/hr
-
C60 km/hr
-
D66 km/hr
Answer
Correct Answer: 60 km/hr
Explanation
We are given:
- Length of each train = 100 m
- Time to cross each other = 8 seconds
- One train is twice as fast as the other
Step 1: Let the slower train's speed be x m/sThen the faster train's speed = 2x m/sRelative speed = x + 2x = 3x
Step 2: Use distance = speed × timeTotal distance = 100 + 100 = 200 m3x × 8 = 200 → x = 25 / 3 ≈ 8.33 m/s
Step 3: Convert faster train's speed to km/hr2x = 2 × 8.33 ≈ 16.66 m/s= 16.66 × (18/5) ≈ 60 km/hr
Final Answer:The speed of the faster train is 60 km/hr