Find the speed of train?

Question

2 trains are moving on 2 parallel tracks but in opposite directions.A person sitting in the train moving at 80 Km/Hr passes the train in 18 sec, If the length of the second train in 1000 m its speed is?

Answer 1

80km/h/3.6

=22.2222m/s

Total crossing speed

1000/18

=55.55m/s

Minus the speed of the first train

55.555-22.2222

=33.3333m/s

*3.6

=120km/h - Exactly!

Answer 2

fast

Answer 3

77.7m/sec

Answer 4

80 k/hr = 80,000 m/hr

Divide by 3600 to get speed in seconds, so

Speed of 1st train = 22.22 km/second

(22.22 + speed of second train) x 18 seconds = 1000 m

(22.22 + speed of 2nd train) = 55.56 m/second

speed of 2nd train = 33.34 m/second

= 120,024 m/hr, divide by 1000 to get km/hr

= approximately 120 km/hr