Multiple choice general knowledge math & puzzles

Two trains move in the same direction at 50 kmph and 32 kmph respectively. A man in the slower train observes the 15 seconds elapse before the faster train completely passes by him.What is the length (in mts.) of faster train ?

  1. 100

  2. 75

  3. 125

  4. 150

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Relative speed in the same direction is the difference: 50 - 32 = 18 kmph. Converting to m/s: 18 * (5/18) = 5 m/s. Distance = Speed * Time = 5 m/s * 15 s = 75 meters.