2015 · Q10
Two trains are moving in the same direction at 1.5 km/minute and 60 km/ hour respectively. A man in the faster train observes that it takes 27 seconds to cross the slower train. The length of the slower train is
Elementary MathematicsNumber System
- A225 m
- B230 m
- C240 m
- D250 m
Explanation
1.5 km/min = 90 km/h, so the relative speed is 90 - 60 = 30 km/h = 25/3 m/s. In 27 s the faster train gains 27 x 25/3 = 225 m on the slower train, which is the slower train's length. Hence option (a).