Aptitude Day 295

Answers of Day 294: 1. 50 m. 

                                     2. 36 seconds.

Problems on Trains:

1. A train 150 m long passes a man, running at 4 km/hr in the same direction in which the train is going, in 30 seconds. The speed of the train is:

Solution:

                  x-4 = 150*18/5 *1/30

                  x = 34 km/hr.

2. 2 trains of equal length are running on parallel lines in the same direction at 60 km/hr and 40 km/hr. The faster train passes the slower train in 36 seconds. The length of each train is:

Solution:

                  Relative speed = 60-40 =20 km/hr 

                                                        = 20*5/18 

                                                        = 50/9 m/s.

                  (x+x)/36 =50/9

                   Length, x = 100 m.