Question

Two trains move in the same direction at speeds 50 kmph and 32 kmph respectively. A man in the slower train observes that 15 seconds elapse before the faster train completely passes by him. What is the length of faster train?
(a) 100m (b) 75m (c) 120m (d) 50m

Answer 1

Answer: 75 m

Step-by-step explanation:

Speed of train A = 50 km/hr × 5/18

= 13.8 m/s

Speed of train B = 32 × 5/18

= 8.8 m/s

Since, Distance = speed × time

Lenght of the faster train = distance of train A covered in 15 seconds- distance of train B covered in 15 seconds

= speed A × time - speed B × time

= 13.8 × 15 - 8.8 × 15

= 207 - 132

= 75 m

Hope it helps you!